objectaddress.c

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/*-------------------------------------------------------------------------
 *
 * objectaddress.c
 *    functions for working with ObjectAddresses
 *
 * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 *
 * IDENTIFICATION
 *    src/backend/catalog/objectaddress.c
 *
 *-------------------------------------------------------------------------
 */

#include "postgres.h"

#include "access/genam.h"
#include "access/htup_details.h"
#include "access/relation.h"
#include "access/sysattr.h"
#include "access/table.h"
#include "catalog/catalog.h"
#include "catalog/indexing.h"
#include "catalog/objectaddress.h"
#include "catalog/pg_am.h"
#include "catalog/pg_amop.h"
#include "catalog/pg_amproc.h"
#include "catalog/pg_attrdef.h"
#include "catalog/pg_authid.h"
#include "catalog/pg_cast.h"
#include "catalog/pg_collation.h"
#include "catalog/pg_constraint.h"
#include "catalog/pg_conversion.h"
#include "catalog/pg_database.h"
#include "catalog/pg_default_acl.h"
#include "catalog/pg_enum.h"
#include "catalog/pg_event_trigger.h"
#include "catalog/pg_extension.h"
#include "catalog/pg_foreign_data_wrapper.h"
#include "catalog/pg_foreign_server.h"
#include "catalog/pg_language.h"
#include "catalog/pg_largeobject.h"
#include "catalog/pg_largeobject_metadata.h"
#include "catalog/pg_namespace.h"
#include "catalog/pg_opclass.h"
#include "catalog/pg_operator.h"
#include "catalog/pg_opfamily.h"
#include "catalog/pg_policy.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_publication.h"
#include "catalog/pg_publication_rel.h"
#include "catalog/pg_rewrite.h"
#include "catalog/pg_statistic_ext.h"
#include "catalog/pg_subscription.h"
#include "catalog/pg_tablespace.h"
#include "catalog/pg_transform.h"
#include "catalog/pg_trigger.h"
#include "catalog/pg_ts_config.h"
#include "catalog/pg_ts_dict.h"
#include "catalog/pg_ts_parser.h"
#include "catalog/pg_ts_template.h"
#include "catalog/pg_type.h"
#include "catalog/pg_user_mapping.h"
#include "commands/dbcommands.h"
#include "commands/defrem.h"
#include "commands/event_trigger.h"
#include "commands/extension.h"
#include "commands/policy.h"
#include "commands/proclang.h"
#include "commands/tablespace.h"
#include "commands/trigger.h"
#include "foreign/foreign.h"
#include "funcapi.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "parser/parse_func.h"
#include "parser/parse_oper.h"
#include "parser/parse_type.h"
#include "rewrite/rewriteSupport.h"
#include "storage/large_object.h"
#include "storage/lmgr.h"
#include "storage/sinval.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/regproc.h"
#include "utils/syscache.h"

/*
 * ObjectProperty
 *
 * This array provides a common part of system object structure; to help
 * consolidate routines to handle various kind of object classes.
 */
typedef struct
{
    Oid         class_oid;      /* oid of catalog */
    Oid         oid_index_oid;  /* oid of index on system oid column */
    int         oid_catcache_id;    /* id of catcache on system oid column  */
    int         name_catcache_id;   /* id of catcache on (name,namespace), or
                                     * (name) if the object does not live in a
                                     * namespace */
    AttrNumber  attnum_oid;     /* attribute number of oid column */
    AttrNumber  attnum_name;    /* attnum of name field */
    AttrNumber  attnum_namespace;   /* attnum of namespace field */
    AttrNumber  attnum_owner;   /* attnum of owner field */
    AttrNumber  attnum_acl;     /* attnum of acl field */
    ObjectType  objtype;        /* OBJECT_* of this object type */
    bool        is_nsp_name_unique; /* can the nsp/name combination (or name
                                     * alone, if there's no namespace) be
                                     * considered a unique identifier for an
                                     * object of this class? */
} ObjectPropertyType;

static const ObjectPropertyType ObjectProperty[] =
{
    {
        AccessMethodRelationId,
        AmOidIndexId,
        AMOID,
        AMNAME,
        Anum_pg_am_oid,
        Anum_pg_am_amname,
        InvalidAttrNumber,
        InvalidAttrNumber,
        InvalidAttrNumber,
        -1,
        true
    },
    {
        CastRelationId,
        CastOidIndexId,
        -1,
        -1,
        Anum_pg_cast_oid,
        InvalidAttrNumber,
        InvalidAttrNumber,
        InvalidAttrNumber,
        InvalidAttrNumber,
        -1,
        false
    },
    {
        CollationRelationId,
        CollationOidIndexId,
        COLLOID,
        -1,                     /* COLLNAMEENCNSP also takes encoding */
        Anum_pg_collation_oid,
        Anum_pg_collation_collname,
        Anum_pg_collation_collnamespace,
        Anum_pg_collation_collowner,
        InvalidAttrNumber,
        OBJECT_COLLATION,
        true
    },
    {
        ConstraintRelationId,
        ConstraintOidIndexId,
        CONSTROID,
        -1,
        Anum_pg_constraint_oid,
        Anum_pg_constraint_conname,
        Anum_pg_constraint_connamespace,
        InvalidAttrNumber,
        InvalidAttrNumber,
        -1,
        false
    },
    {
        ConversionRelationId,
        ConversionOidIndexId,
        CONVOID,
        CONNAMENSP,
        Anum_pg_conversion_oid,
        Anum_pg_conversion_conname,
        Anum_pg_conversion_connamespace,
        Anum_pg_conversion_conowner,
        InvalidAttrNumber,
        OBJECT_CONVERSION,
        true
    },
    {
        DatabaseRelationId,
        DatabaseOidIndexId,
        DATABASEOID,
        -1,
        Anum_pg_database_oid,
        Anum_pg_database_datname,
        InvalidAttrNumber,
        Anum_pg_database_datdba,
        Anum_pg_database_datacl,
        OBJECT_DATABASE,
        true
    },
    {
        ExtensionRelationId,
        ExtensionOidIndexId,
        -1,
        -1,
        Anum_pg_extension_oid,
        Anum_pg_extension_extname,
        InvalidAttrNumber,      /* extension doesn't belong to extnamespace */
        Anum_pg_extension_extowner,
        InvalidAttrNumber,
        OBJECT_EXTENSION,
        true
    },
    {
        ForeignDataWrapperRelationId,
        ForeignDataWrapperOidIndexId,
        FOREIGNDATAWRAPPEROID,
        FOREIGNDATAWRAPPERNAME,
        Anum_pg_foreign_data_wrapper_oid,
        Anum_pg_foreign_data_wrapper_fdwname,
        InvalidAttrNumber,
        Anum_pg_foreign_data_wrapper_fdwowner,
        Anum_pg_foreign_data_wrapper_fdwacl,
        OBJECT_FDW,
        true
    },
    {
        ForeignServerRelationId,
        ForeignServerOidIndexId,
        FOREIGNSERVEROID,
        FOREIGNSERVERNAME,
        Anum_pg_foreign_server_oid,
        Anum_pg_foreign_server_srvname,
        InvalidAttrNumber,
        Anum_pg_foreign_server_srvowner,
        Anum_pg_foreign_server_srvacl,
        OBJECT_FOREIGN_SERVER,
        true
    },
    {
        ProcedureRelationId,
        ProcedureOidIndexId,
        PROCOID,
        -1,                     /* PROCNAMEARGSNSP also takes argument types */
        Anum_pg_proc_oid,
        Anum_pg_proc_proname,
        Anum_pg_proc_pronamespace,
        Anum_pg_proc_proowner,
        Anum_pg_proc_proacl,
        OBJECT_FUNCTION,
        false
    },
    {
        LanguageRelationId,
        LanguageOidIndexId,
        LANGOID,
        LANGNAME,
        Anum_pg_language_oid,
        Anum_pg_language_lanname,
        InvalidAttrNumber,
        Anum_pg_language_lanowner,
        Anum_pg_language_lanacl,
        OBJECT_LANGUAGE,
        true
    },
    {
        LargeObjectMetadataRelationId,
        LargeObjectMetadataOidIndexId,
        -1,
        -1,
        Anum_pg_largeobject_metadata_oid,
        InvalidAttrNumber,
        InvalidAttrNumber,
        Anum_pg_largeobject_metadata_lomowner,
        Anum_pg_largeobject_metadata_lomacl,
        OBJECT_LARGEOBJECT,
        false
    },
    {
        OperatorClassRelationId,
        OpclassOidIndexId,
        CLAOID,
        -1,                     /* CLAAMNAMENSP also takes opcmethod */
        Anum_pg_opclass_oid,
        Anum_pg_opclass_opcname,
        Anum_pg_opclass_opcnamespace,
        Anum_pg_opclass_opcowner,
        InvalidAttrNumber,
        OBJECT_OPCLASS,
        true
    },
    {
        OperatorRelationId,
        OperatorOidIndexId,
        OPEROID,
        -1,                     /* OPERNAMENSP also takes left and right type */
        Anum_pg_operator_oid,
        Anum_pg_operator_oprname,
        Anum_pg_operator_oprnamespace,
        Anum_pg_operator_oprowner,
        InvalidAttrNumber,
        OBJECT_OPERATOR,
        false
    },
    {
        OperatorFamilyRelationId,
        OpfamilyOidIndexId,
        OPFAMILYOID,
        -1,                     /* OPFAMILYAMNAMENSP also takes opfmethod */
        Anum_pg_opfamily_oid,
        Anum_pg_opfamily_opfname,
        Anum_pg_opfamily_opfnamespace,
        Anum_pg_opfamily_opfowner,
        InvalidAttrNumber,
        OBJECT_OPFAMILY,
        true
    },
    {
        AuthIdRelationId,
        AuthIdOidIndexId,
        AUTHOID,
        AUTHNAME,
        Anum_pg_authid_oid,
        Anum_pg_authid_rolname,
        InvalidAttrNumber,
        InvalidAttrNumber,
        InvalidAttrNumber,
        -1,
        true
    },
    {
        RewriteRelationId,
        RewriteOidIndexId,
        -1,
        -1,
        Anum_pg_rewrite_oid,
        Anum_pg_rewrite_rulename,
        InvalidAttrNumber,
        InvalidAttrNumber,
        InvalidAttrNumber,
        -1,
        false
    },
    {
        NamespaceRelationId,
        NamespaceOidIndexId,
        NAMESPACEOID,
        NAMESPACENAME,
        Anum_pg_namespace_oid,
        Anum_pg_namespace_nspname,
        InvalidAttrNumber,
        Anum_pg_namespace_nspowner,
        Anum_pg_namespace_nspacl,
        OBJECT_SCHEMA,
        true
    },
    {
        RelationRelationId,
        ClassOidIndexId,
        RELOID,
        RELNAMENSP,
        Anum_pg_class_oid,
        Anum_pg_class_relname,
        Anum_pg_class_relnamespace,
        Anum_pg_class_relowner,
        Anum_pg_class_relacl,
        OBJECT_TABLE,
        true
    },
    {
        TableSpaceRelationId,
        TablespaceOidIndexId,
        TABLESPACEOID,
        -1,
        Anum_pg_tablespace_oid,
        Anum_pg_tablespace_spcname,
        InvalidAttrNumber,
        Anum_pg_tablespace_spcowner,
        Anum_pg_tablespace_spcacl,
        OBJECT_TABLESPACE,
        true
    },
    {
        TransformRelationId,
        TransformOidIndexId,
        TRFOID,
        InvalidAttrNumber,
        Anum_pg_transform_oid
    },
    {
        TriggerRelationId,
        TriggerOidIndexId,
        -1,
        -1,
        Anum_pg_trigger_oid,
        Anum_pg_trigger_tgname,
        InvalidAttrNumber,
        InvalidAttrNumber,
        InvalidAttrNumber,
        -1,
        false
    },
    {
        PolicyRelationId,
        PolicyOidIndexId,
        -1,
        -1,
        Anum_pg_policy_oid,
        Anum_pg_policy_polname,
        InvalidAttrNumber,
        InvalidAttrNumber,
        InvalidAttrNumber,
        -1,
        false
    },
    {
        EventTriggerRelationId,
        EventTriggerOidIndexId,
        EVENTTRIGGEROID,
        EVENTTRIGGERNAME,
        Anum_pg_event_trigger_oid,
        Anum_pg_event_trigger_evtname,
        InvalidAttrNumber,
        Anum_pg_event_trigger_evtowner,
        InvalidAttrNumber,
        OBJECT_EVENT_TRIGGER,
        true
    },
    {
        TSConfigRelationId,
        TSConfigOidIndexId,
        TSCONFIGOID,
        TSCONFIGNAMENSP,
        Anum_pg_ts_config_oid,
        Anum_pg_ts_config_cfgname,
        Anum_pg_ts_config_cfgnamespace,
        Anum_pg_ts_config_cfgowner,
        InvalidAttrNumber,
        OBJECT_TSCONFIGURATION,
        true
    },
    {
        TSDictionaryRelationId,
        TSDictionaryOidIndexId,
        TSDICTOID,
        TSDICTNAMENSP,
        Anum_pg_ts_dict_oid,
        Anum_pg_ts_dict_dictname,
        Anum_pg_ts_dict_dictnamespace,
        Anum_pg_ts_dict_dictowner,
        InvalidAttrNumber,
        OBJECT_TSDICTIONARY,
        true
    },
    {
        TSParserRelationId,
        TSParserOidIndexId,
        TSPARSEROID,
        TSPARSERNAMENSP,
        Anum_pg_ts_parser_oid,
        Anum_pg_ts_parser_prsname,
        Anum_pg_ts_parser_prsnamespace,
        InvalidAttrNumber,
        InvalidAttrNumber,
        -1,
        true
    },
    {
        TSTemplateRelationId,
        TSTemplateOidIndexId,
        TSTEMPLATEOID,
        TSTEMPLATENAMENSP,
        Anum_pg_ts_template_oid,
        Anum_pg_ts_template_tmplname,
        Anum_pg_ts_template_tmplnamespace,
        InvalidAttrNumber,
        InvalidAttrNumber,
        -1,
        true,
    },
    {
        TypeRelationId,
        TypeOidIndexId,
        TYPEOID,
        TYPENAMENSP,
        Anum_pg_type_oid,
        Anum_pg_type_typname,
        Anum_pg_type_typnamespace,
        Anum_pg_type_typowner,
        Anum_pg_type_typacl,
        OBJECT_TYPE,
        true
    },
    {
        PublicationRelationId,
        PublicationObjectIndexId,
        PUBLICATIONOID,
        PUBLICATIONNAME,
        Anum_pg_publication_oid,
        Anum_pg_publication_pubname,
        InvalidAttrNumber,
        Anum_pg_publication_pubowner,
        InvalidAttrNumber,
        OBJECT_PUBLICATION,
        true
    },
    {
        SubscriptionRelationId,
        SubscriptionObjectIndexId,
        SUBSCRIPTIONOID,
        SUBSCRIPTIONNAME,
        Anum_pg_subscription_oid,
        Anum_pg_subscription_subname,
        InvalidAttrNumber,
        Anum_pg_subscription_subowner,
        InvalidAttrNumber,
        OBJECT_SUBSCRIPTION,
        true
    },
    {
        StatisticExtRelationId,
        StatisticExtOidIndexId,
        STATEXTOID,
        STATEXTNAMENSP,
        Anum_pg_statistic_ext_oid,
        Anum_pg_statistic_ext_stxname,
        Anum_pg_statistic_ext_stxnamespace,
        Anum_pg_statistic_ext_stxowner,
        InvalidAttrNumber,      /* no ACL (same as relation) */
        OBJECT_STATISTIC_EXT,
        true
    }
};

/*
 * This struct maps the string object types as returned by
 * getObjectTypeDescription into ObjectType enum values.  Note that some enum
 * values can be obtained by different names, and that some string object types
 * do not have corresponding values in the output enum.  The user of this map
 * must be careful to test for invalid values being returned.
 *
 * To ease maintenance, this follows the order of getObjectTypeDescription.
 */
static const struct object_type_map
{
    const char *tm_name;
    ObjectType  tm_type;
}

            ObjectTypeMap[] =
{
    /* OCLASS_CLASS, all kinds of relations */
    {
        "table", OBJECT_TABLE
    },
    {
        "index", OBJECT_INDEX
    },
    {
        "sequence", OBJECT_SEQUENCE
    },
    {
        "toast table", -1
    },                          /* unmapped */
    {
        "view", OBJECT_VIEW
    },
    {
        "materialized view", OBJECT_MATVIEW
    },
    {
        "composite type", -1
    },                          /* unmapped */
    {
        "foreign table", OBJECT_FOREIGN_TABLE
    },
    {
        "table column", OBJECT_COLUMN
    },
    {
        "index column", -1
    },                          /* unmapped */
    {
        "sequence column", -1
    },                          /* unmapped */
    {
        "toast table column", -1
    },                          /* unmapped */
    {
        "view column", -1
    },                          /* unmapped */
    {
        "materialized view column", -1
    },                          /* unmapped */
    {
        "composite type column", -1
    },                          /* unmapped */
    {
        "foreign table column", OBJECT_COLUMN
    },
    /* OCLASS_PROC */
    {
        "aggregate", OBJECT_AGGREGATE
    },
    {
        "function", OBJECT_FUNCTION
    },
    {
        "procedure", OBJECT_PROCEDURE
    },
    /* OCLASS_TYPE */
    {
        "type", OBJECT_TYPE
    },
    /* OCLASS_CAST */
    {
        "cast", OBJECT_CAST
    },
    /* OCLASS_COLLATION */
    {
        "collation", OBJECT_COLLATION
    },
    /* OCLASS_CONSTRAINT */
    {
        "table constraint", OBJECT_TABCONSTRAINT
    },
    {
        "domain constraint", OBJECT_DOMCONSTRAINT
    },
    /* OCLASS_CONVERSION */
    {
        "conversion", OBJECT_CONVERSION
    },
    /* OCLASS_DEFAULT */
    {
        "default value", OBJECT_DEFAULT
    },
    /* OCLASS_LANGUAGE */
    {
        "language", OBJECT_LANGUAGE
    },
    /* OCLASS_LARGEOBJECT */
    {
        "large object", OBJECT_LARGEOBJECT
    },
    /* OCLASS_OPERATOR */
    {
        "operator", OBJECT_OPERATOR
    },
    /* OCLASS_OPCLASS */
    {
        "operator class", OBJECT_OPCLASS
    },
    /* OCLASS_OPFAMILY */
    {
        "operator family", OBJECT_OPFAMILY
    },
    /* OCLASS_AM */
    {
        "access method", OBJECT_ACCESS_METHOD
    },
    /* OCLASS_AMOP */
    {
        "operator of access method", OBJECT_AMOP
    },
    /* OCLASS_AMPROC */
    {
        "function of access method", OBJECT_AMPROC
    },
    /* OCLASS_REWRITE */
    {
        "rule", OBJECT_RULE
    },
    /* OCLASS_TRIGGER */
    {
        "trigger", OBJECT_TRIGGER
    },
    /* OCLASS_SCHEMA */
    {
        "schema", OBJECT_SCHEMA
    },
    /* OCLASS_TSPARSER */
    {
        "text search parser", OBJECT_TSPARSER
    },
    /* OCLASS_TSDICT */
    {
        "text search dictionary", OBJECT_TSDICTIONARY
    },
    /* OCLASS_TSTEMPLATE */
    {
        "text search template", OBJECT_TSTEMPLATE
    },
    /* OCLASS_TSCONFIG */
    {
        "text search configuration", OBJECT_TSCONFIGURATION
    },
    /* OCLASS_ROLE */
    {
        "role", OBJECT_ROLE
    },
    /* OCLASS_DATABASE */
    {
        "database", OBJECT_DATABASE
    },
    /* OCLASS_TBLSPACE */
    {
        "tablespace", OBJECT_TABLESPACE
    },
    /* OCLASS_FDW */
    {
        "foreign-data wrapper", OBJECT_FDW
    },
    /* OCLASS_FOREIGN_SERVER */
    {
        "server", OBJECT_FOREIGN_SERVER
    },
    /* OCLASS_USER_MAPPING */
    {
        "user mapping", OBJECT_USER_MAPPING
    },
    /* OCLASS_DEFACL */
    {
        "default acl", OBJECT_DEFACL
    },
    /* OCLASS_EXTENSION */
    {
        "extension", OBJECT_EXTENSION
    },
    /* OCLASS_EVENT_TRIGGER */
    {
        "event trigger", OBJECT_EVENT_TRIGGER
    },
    /* OCLASS_POLICY */
    {
        "policy", OBJECT_POLICY
    },
    /* OCLASS_PUBLICATION */
    {
        "publication", OBJECT_PUBLICATION
    },
    /* OCLASS_PUBLICATION_REL */
    {
        "publication relation", OBJECT_PUBLICATION_REL
    },
    /* OCLASS_SUBSCRIPTION */
    {
        "subscription", OBJECT_SUBSCRIPTION
    },
    /* OCLASS_TRANSFORM */
    {
        "transform", OBJECT_TRANSFORM
    },
    /* OBJECT_STATISTIC_EXT */
    {
        "statistics object", OBJECT_STATISTIC_EXT
    }
};

const ObjectAddress InvalidObjectAddress =
{
    InvalidOid,
    InvalidOid,
    0
};

static ObjectAddress get_object_address_unqualified(ObjectType objtype,
                                                    Value *strval, bool missing_ok);
static ObjectAddress get_relation_by_qualified_name(ObjectType objtype,
                                                    List *object, Relation *relp,
                                                    LOCKMODE lockmode, bool missing_ok);
static ObjectAddress get_object_address_relobject(ObjectType objtype,
                                                  List *object, Relation *relp, bool missing_ok);
static ObjectAddress get_object_address_attribute(ObjectType objtype,
                                                  List *object, Relation *relp,
                                                  LOCKMODE lockmode, bool missing_ok);
static ObjectAddress get_object_address_attrdef(ObjectType objtype,
                                                List *object, Relation *relp, LOCKMODE lockmode,
                                                bool missing_ok);
static ObjectAddress get_object_address_type(ObjectType objtype,
                                             TypeName *typename, bool missing_ok);
static ObjectAddress get_object_address_opcf(ObjectType objtype, List *object,
                                             bool missing_ok);
static ObjectAddress get_object_address_opf_member(ObjectType objtype,
                                                   List *object, bool missing_ok);

static ObjectAddress get_object_address_usermapping(List *object,
                                                    bool missing_ok);
static ObjectAddress get_object_address_publication_rel(List *object,
                                                        Relation *relp,
                                                        bool missing_ok);
static ObjectAddress get_object_address_defacl(List *object,
                                               bool missing_ok);
static const ObjectPropertyType *get_object_property_data(Oid class_id);

static void getRelationDescription(StringInfo buffer, Oid relid);
static void getOpFamilyDescription(StringInfo buffer, Oid opfid);
static void getRelationTypeDescription(StringInfo buffer, Oid relid,
                                       int32 objectSubId);
static void getProcedureTypeDescription(StringInfo buffer, Oid procid);
static void getConstraintTypeDescription(StringInfo buffer, Oid constroid);
static void getOpFamilyIdentity(StringInfo buffer, Oid opfid, List **object);
static void getRelationIdentity(StringInfo buffer, Oid relid, List **object);

/*
 * Translate an object name and arguments (as passed by the parser) to an
 * ObjectAddress.
 *
 * The returned object will be locked using the specified lockmode.  If a
 * sub-object is looked up, the parent object will be locked instead.
 *
 * If the object is a relation or a child object of a relation (e.g. an
 * attribute or constraint), the relation is also opened and *relp receives
 * the open relcache entry pointer; otherwise, *relp is set to NULL.  This
 * is a bit grotty but it makes life simpler, since the caller will
 * typically need the relcache entry too.  Caller must close the relcache
 * entry when done with it.  The relation is locked with the specified lockmode
 * if the target object is the relation itself or an attribute, but for other
 * child objects, only AccessShareLock is acquired on the relation.
 *
 * If the object is not found, an error is thrown, unless missing_ok is
 * true.  In this case, no lock is acquired, relp is set to NULL, and the
 * returned address has objectId set to InvalidOid.
 *
 * We don't currently provide a function to release the locks acquired here;
 * typically, the lock must be held until commit to guard against a concurrent
 * drop operation.
 *
 * Note: If the object is not found, we don't give any indication of the
 * reason.  (It might have been a missing schema if the name was qualified, or
 * a nonexistent type name in case of a cast, function or operator; etc).
 * Currently there is only one caller that might be interested in such info, so
 * we don't spend much effort here.  If more callers start to care, it might be
 * better to add some support for that in this function.
 */
ObjectAddress
get_object_address(ObjectType objtype, Node *object,
                   Relation *relp, LOCKMODE lockmode, bool missing_ok)
{
    ObjectAddress address;
    ObjectAddress old_address = {InvalidOid, InvalidOid, 0};
    Relation    relation = NULL;
    uint64      inval_count;

    /* Some kind of lock must be taken. */
    Assert(lockmode != NoLock);

    for (;;)
    {
        /*
         * Remember this value, so that, after looking up the object name and
         * locking it, we can check whether any invalidation messages have
         * been processed that might require a do-over.
         */
        inval_count = SharedInvalidMessageCounter;

        /* Look up object address. */
        switch (objtype)
        {
            case OBJECT_INDEX:
            case OBJECT_SEQUENCE:
            case OBJECT_TABLE:
            case OBJECT_VIEW:
            case OBJECT_MATVIEW:
            case OBJECT_FOREIGN_TABLE:
                address =
                    get_relation_by_qualified_name(objtype, castNode(List, object),
                                                   &relation, lockmode,
                                                   missing_ok);
                break;
            case OBJECT_COLUMN:
                address =
                    get_object_address_attribute(objtype, castNode(List, object),
                                                 &relation, lockmode,
                                                 missing_ok);
                break;
            case OBJECT_DEFAULT:
                address =
                    get_object_address_attrdef(objtype, castNode(List, object),
                                               &relation, lockmode,
                                               missing_ok);
                break;
            case OBJECT_RULE:
            case OBJECT_TRIGGER:
            case OBJECT_TABCONSTRAINT:
            case OBJECT_POLICY:
                address = get_object_address_relobject(objtype, castNode(List, object),
                                                       &relation, missing_ok);
                break;
            case OBJECT_DOMCONSTRAINT:
                {
                    List       *objlist;
                    ObjectAddress domaddr;
                    char       *constrname;

                    objlist = castNode(List, object);
                    domaddr = get_object_address_type(OBJECT_DOMAIN,
                                                      linitial_node(TypeName, objlist),
                                                      missing_ok);
                    constrname = strVal(lsecond(objlist));

                    address.classId = ConstraintRelationId;
                    address.objectId = get_domain_constraint_oid(domaddr.objectId,
                                                                 constrname, missing_ok);
                    address.objectSubId = 0;

                }
                break;
            case OBJECT_DATABASE:
            case OBJECT_EXTENSION:
            case OBJECT_TABLESPACE:
            case OBJECT_ROLE:
            case OBJECT_SCHEMA:
            case OBJECT_LANGUAGE:
            case OBJECT_FDW:
            case OBJECT_FOREIGN_SERVER:
            case OBJECT_EVENT_TRIGGER:
            case OBJECT_ACCESS_METHOD:
            case OBJECT_PUBLICATION:
            case OBJECT_SUBSCRIPTION:
                address = get_object_address_unqualified(objtype,
                                                         (Value *) object, missing_ok);
                break;
            case OBJECT_TYPE:
            case OBJECT_DOMAIN:
                address = get_object_address_type(objtype, castNode(TypeName, object), missing_ok);
                break;
            case OBJECT_AGGREGATE:
            case OBJECT_FUNCTION:
            case OBJECT_PROCEDURE:
            case OBJECT_ROUTINE:
                address.classId = ProcedureRelationId;
                address.objectId = LookupFuncWithArgs(objtype, castNode(ObjectWithArgs, object), missing_ok);
                address.objectSubId = 0;
                break;
            case OBJECT_OPERATOR:
                address.classId = OperatorRelationId;
                address.objectId = LookupOperWithArgs(castNode(ObjectWithArgs, object), missing_ok);
                address.objectSubId = 0;
                break;
            case OBJECT_COLLATION:
                address.classId = CollationRelationId;
                address.objectId = get_collation_oid(castNode(List, object), missing_ok);
                address.objectSubId = 0;
                break;
            case OBJECT_CONVERSION:
                address.classId = ConversionRelationId;
                address.objectId = get_conversion_oid(castNode(List, object), missing_ok);
                address.objectSubId = 0;
                break;
            case OBJECT_OPCLASS:
            case OBJECT_OPFAMILY:
                address = get_object_address_opcf(objtype, castNode(List, object), missing_ok);
                break;
            case OBJECT_AMOP:
            case OBJECT_AMPROC:
                address = get_object_address_opf_member(objtype, castNode(List, object), missing_ok);
                break;
            case OBJECT_LARGEOBJECT:
                address.classId = LargeObjectRelationId;
                address.objectId = oidparse(object);
                address.objectSubId = 0;
                if (!LargeObjectExists(address.objectId))
                {
                    if (!missing_ok)
                        ereport(ERROR,
                                (errcode(ERRCODE_UNDEFINED_OBJECT),
                                 errmsg("large object %u does not exist",
                                        address.objectId)));
                }
                break;
            case OBJECT_CAST:
                {
                    TypeName   *sourcetype = linitial_node(TypeName, castNode(List, object));
                    TypeName   *targettype = lsecond_node(TypeName, castNode(List, object));
                    Oid         sourcetypeid;
                    Oid         targettypeid;

                    sourcetypeid = LookupTypeNameOid(NULL, sourcetype, missing_ok);
                    targettypeid = LookupTypeNameOid(NULL, targettype, missing_ok);
                    address.classId = CastRelationId;
                    address.objectId =
                        get_cast_oid(sourcetypeid, targettypeid, missing_ok);
                    address.objectSubId = 0;
                }
                break;
            case OBJECT_TRANSFORM:
                {
                    TypeName   *typename = linitial_node(TypeName, castNode(List, object));
                    char       *langname = strVal(lsecond(castNode(List, object)));
                    Oid         type_id = LookupTypeNameOid(NULL, typename, missing_ok);
                    Oid         lang_id = get_language_oid(langname, missing_ok);

                    address.classId = TransformRelationId;
                    address.objectId =
                        get_transform_oid(type_id, lang_id, missing_ok);
                    address.objectSubId = 0;
                }
                break;
            case OBJECT_TSPARSER:
                address.classId = TSParserRelationId;
                address.objectId = get_ts_parser_oid(castNode(List, object), missing_ok);
                address.objectSubId = 0;
                break;
            case OBJECT_TSDICTIONARY:
                address.classId = TSDictionaryRelationId;
                address.objectId = get_ts_dict_oid(castNode(List, object), missing_ok);
                address.objectSubId = 0;
                break;
            case OBJECT_TSTEMPLATE:
                address.classId = TSTemplateRelationId;
                address.objectId = get_ts_template_oid(castNode(List, object), missing_ok);
                address.objectSubId = 0;
                break;
            case OBJECT_TSCONFIGURATION:
                address.classId = TSConfigRelationId;
                address.objectId = get_ts_config_oid(castNode(List, object), missing_ok);
                address.objectSubId = 0;
                break;
            case OBJECT_USER_MAPPING:
                address = get_object_address_usermapping(castNode(List, object),
                                                         missing_ok);
                break;
            case OBJECT_PUBLICATION_REL:
                address = get_object_address_publication_rel(castNode(List, object),
                                                             &relation,
                                                             missing_ok);
                break;
            case OBJECT_DEFACL:
                address = get_object_address_defacl(castNode(List, object),
                                                    missing_ok);
                break;
            case OBJECT_STATISTIC_EXT:
                address.classId = StatisticExtRelationId;
                address.objectId = get_statistics_object_oid(castNode(List, object),
                                                             missing_ok);
                address.objectSubId = 0;
                break;
            default:
                elog(ERROR, "unrecognized objtype: %d", (int) objtype);
                /* placate compiler, in case it thinks elog might return */
                address.classId = InvalidOid;
                address.objectId = InvalidOid;
                address.objectSubId = 0;
        }

        /*
         * If we could not find the supplied object, return without locking.
         */
        if (!OidIsValid(address.objectId))
        {
            Assert(missing_ok);
            return address;
        }

        /*
         * If we're retrying, see if we got the same answer as last time.  If
         * so, we're done; if not, we locked the wrong thing, so give up our
         * lock.
         */
        if (OidIsValid(old_address.classId))
        {
            if (old_address.classId == address.classId
                && old_address.objectId == address.objectId
                && old_address.objectSubId == address.objectSubId)
                break;
            if (old_address.classId != RelationRelationId)
            {
                if (IsSharedRelation(old_address.classId))
                    UnlockSharedObject(old_address.classId,
                                       old_address.objectId,
                                       0, lockmode);
                else
                    UnlockDatabaseObject(old_address.classId,
                                         old_address.objectId,
                                         0, lockmode);
            }
        }

        /*
         * If we're dealing with a relation or attribute, then the relation is
         * already locked.  Otherwise, we lock it now.
         */
        if (address.classId != RelationRelationId)
        {
            if (IsSharedRelation(address.classId))
                LockSharedObject(address.classId, address.objectId, 0,
                                 lockmode);
            else
                LockDatabaseObject(address.classId, address.objectId, 0,
                                   lockmode);
        }

        /*
         * At this point, we've resolved the name to an OID and locked the
         * corresponding database object.  However, it's possible that by the
         * time we acquire the lock on the object, concurrent DDL has modified
         * the database in such a way that the name we originally looked up no
         * longer resolves to that OID.
         *
         * We can be certain that this isn't an issue if (a) no shared
         * invalidation messages have been processed or (b) we've locked a
         * relation somewhere along the line.  All the relation name lookups
         * in this module ultimately use RangeVarGetRelid() to acquire a
         * relation lock, and that function protects against the same kinds of
         * races we're worried about here.  Even when operating on a
         * constraint, rule, or trigger, we still acquire AccessShareLock on
         * the relation, which is enough to freeze out any concurrent DDL.
         *
         * In all other cases, however, it's possible that the name we looked
         * up no longer refers to the object we locked, so we retry the lookup
         * and see whether we get the same answer.
         */
        if (inval_count == SharedInvalidMessageCounter || relation != NULL)
            break;
        old_address = address;
    }

    /* Return the object address and the relation. */
    *relp = relation;
    return address;
}

/*
 * Return an ObjectAddress based on a RangeVar and an object name. The
 * name of the relation identified by the RangeVar is prepended to the
 * (possibly empty) list passed in as object. This is useful to find
 * the ObjectAddress of objects that depend on a relation. All other
 * considerations are exactly as for get_object_address above.
 */
ObjectAddress
get_object_address_rv(ObjectType objtype, RangeVar *rel, List *object,
                      Relation *relp, LOCKMODE lockmode,
                      bool missing_ok)
{
    if (rel)
    {
        object = lcons(makeString(rel->relname), object);
        if (rel->schemaname)
            object = lcons(makeString(rel->schemaname), object);
        if (rel->catalogname)
            object = lcons(makeString(rel->catalogname), object);
    }

    return get_object_address(objtype, (Node *) object,
                              relp, lockmode, missing_ok);
}

/*
 * Find an ObjectAddress for a type of object that is identified by an
 * unqualified name.
 */
static ObjectAddress
get_object_address_unqualified(ObjectType objtype,
                               Value *strval, bool missing_ok)
{
    const char *name;
    ObjectAddress address;

    name = strVal(strval);

    /* Translate name to OID. */
    switch (objtype)
    {
        case OBJECT_ACCESS_METHOD:
            address.classId = AccessMethodRelationId;
            address.objectId = get_am_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_DATABASE:
            address.classId = DatabaseRelationId;
            address.objectId = get_database_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_EXTENSION:
            address.classId = ExtensionRelationId;
            address.objectId = get_extension_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_TABLESPACE:
            address.classId = TableSpaceRelationId;
            address.objectId = get_tablespace_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_ROLE:
            address.classId = AuthIdRelationId;
            address.objectId = get_role_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_SCHEMA:
            address.classId = NamespaceRelationId;
            address.objectId = get_namespace_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_LANGUAGE:
            address.classId = LanguageRelationId;
            address.objectId = get_language_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_FDW:
            address.classId = ForeignDataWrapperRelationId;
            address.objectId = get_foreign_data_wrapper_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_FOREIGN_SERVER:
            address.classId = ForeignServerRelationId;
            address.objectId = get_foreign_server_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_EVENT_TRIGGER:
            address.classId = EventTriggerRelationId;
            address.objectId = get_event_trigger_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_PUBLICATION:
            address.classId = PublicationRelationId;
            address.objectId = get_publication_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_SUBSCRIPTION:
            address.classId = SubscriptionRelationId;
            address.objectId = get_subscription_oid(name, missing_ok);
            address.objectSubId = 0;
            break;
        default:
            elog(ERROR, "unrecognized objtype: %d", (int) objtype);
            /* placate compiler, which doesn't know elog won't return */
            address.classId = InvalidOid;
            address.objectId = InvalidOid;
            address.objectSubId = 0;
    }

    return address;
}

/*
 * Locate a relation by qualified name.
 */
static ObjectAddress
get_relation_by_qualified_name(ObjectType objtype, List *object,
                               Relation *relp, LOCKMODE lockmode,
                               bool missing_ok)
{
    Relation    relation;
    ObjectAddress address;

    address.classId = RelationRelationId;
    address.objectId = InvalidOid;
    address.objectSubId = 0;

    relation = relation_openrv_extended(makeRangeVarFromNameList(object),
                                        lockmode, missing_ok);
    if (!relation)
        return address;

    switch (objtype)
    {
        case OBJECT_INDEX:
            if (relation->rd_rel->relkind != RELKIND_INDEX &&
                relation->rd_rel->relkind != RELKIND_PARTITIONED_INDEX)
                ereport(ERROR,
                        (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                         errmsg("\"%s\" is not an index",
                                RelationGetRelationName(relation))));
            break;
        case OBJECT_SEQUENCE:
            if (relation->rd_rel->relkind != RELKIND_SEQUENCE)
                ereport(ERROR,
                        (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                         errmsg("\"%s\" is not a sequence",
                                RelationGetRelationName(relation))));
            break;
        case OBJECT_TABLE:
            if (relation->rd_rel->relkind != RELKIND_RELATION &&
                relation->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
                ereport(ERROR,
                        (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                         errmsg("\"%s\" is not a table",
                                RelationGetRelationName(relation))));
            break;
        case OBJECT_VIEW:
            if (relation->rd_rel->relkind != RELKIND_VIEW)
                ereport(ERROR,
                        (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                         errmsg("\"%s\" is not a view",
                                RelationGetRelationName(relation))));
            break;
        case OBJECT_MATVIEW:
            if (relation->rd_rel->relkind != RELKIND_MATVIEW)
                ereport(ERROR,
                        (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                         errmsg("\"%s\" is not a materialized view",
                                RelationGetRelationName(relation))));
            break;
        case OBJECT_FOREIGN_TABLE:
            if (relation->rd_rel->relkind != RELKIND_FOREIGN_TABLE)
                ereport(ERROR,
                        (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                         errmsg("\"%s\" is not a foreign table",
                                RelationGetRelationName(relation))));
            break;
        default:
            elog(ERROR, "unrecognized objtype: %d", (int) objtype);
            break;
    }

    /* Done. */
    address.objectId = RelationGetRelid(relation);
    *relp = relation;

    return address;
}

/*
 * Find object address for an object that is attached to a relation.
 *
 * Note that we take only an AccessShareLock on the relation.  We need not
 * pass down the LOCKMODE from get_object_address(), because that is the lock
 * mode for the object itself, not the relation to which it is attached.
 */
static ObjectAddress
get_object_address_relobject(ObjectType objtype, List *object,
                             Relation *relp, bool missing_ok)
{
    ObjectAddress address;
    Relation    relation = NULL;
    int         nnames;
    const char *depname;
    List       *relname;
    Oid         reloid;

    /* Extract name of dependent object. */
    depname = strVal(llast(object));

    /* Separate relation name from dependent object name. */
    nnames = list_length(object);
    if (nnames < 2)
        ereport(ERROR,
                (errcode(ERRCODE_SYNTAX_ERROR),
                 errmsg("must specify relation and object name")));

    /* Extract relation name and open relation. */
    relname = list_truncate(list_copy(object), nnames - 1);
    relation = table_openrv_extended(makeRangeVarFromNameList(relname),
                                     AccessShareLock,
                                     missing_ok);

    reloid = relation ? RelationGetRelid(relation) : InvalidOid;

    switch (objtype)
    {
        case OBJECT_RULE:
            address.classId = RewriteRelationId;
            address.objectId = relation ?
                get_rewrite_oid(reloid, depname, missing_ok) : InvalidOid;
            address.objectSubId = 0;
            break;
        case OBJECT_TRIGGER:
            address.classId = TriggerRelationId;
            address.objectId = relation ?
                get_trigger_oid(reloid, depname, missing_ok) : InvalidOid;
            address.objectSubId = 0;
            break;
        case OBJECT_TABCONSTRAINT:
            address.classId = ConstraintRelationId;
            address.objectId = relation ?
                get_relation_constraint_oid(reloid, depname, missing_ok) :
                InvalidOid;
            address.objectSubId = 0;
            break;
        case OBJECT_POLICY:
            address.classId = PolicyRelationId;
            address.objectId = relation ?
                get_relation_policy_oid(reloid, depname, missing_ok) :
                InvalidOid;
            address.objectSubId = 0;
            break;
        default:
            elog(ERROR, "unrecognized objtype: %d", (int) objtype);
    }

    /* Avoid relcache leak when object not found. */
    if (!OidIsValid(address.objectId))
    {
        if (relation != NULL)
            table_close(relation, AccessShareLock);

        relation = NULL;        /* department of accident prevention */
        return address;
    }

    /* Done. */
    *relp = relation;
    return address;
}

/*
 * Find the ObjectAddress for an attribute.
 */
static ObjectAddress
get_object_address_attribute(ObjectType objtype, List *object,
                             Relation *relp, LOCKMODE lockmode,
                             bool missing_ok)
{
    ObjectAddress address;
    List       *relname;
    Oid         reloid;
    Relation    relation;
    const char *attname;
    AttrNumber  attnum;

    /* Extract relation name and open relation. */
    if (list_length(object) < 2)
        ereport(ERROR,
                (errcode(ERRCODE_SYNTAX_ERROR),
                 errmsg("column name must be qualified")));
    attname = strVal(lfirst(list_tail(object)));
    relname = list_truncate(list_copy(object), list_length(object) - 1);
    /* XXX no missing_ok support here */
    relation = relation_openrv(makeRangeVarFromNameList(relname), lockmode);
    reloid = RelationGetRelid(relation);

    /* Look up attribute and construct return value. */
    attnum = get_attnum(reloid, attname);
    if (attnum == InvalidAttrNumber)
    {
        if (!missing_ok)
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_COLUMN),
                     errmsg("column \"%s\" of relation \"%s\" does not exist",
                            attname, NameListToString(relname))));

        address.classId = RelationRelationId;
        address.objectId = InvalidOid;
        address.objectSubId = InvalidAttrNumber;
        relation_close(relation, lockmode);
        return address;
    }

    address.classId = RelationRelationId;
    address.objectId = reloid;
    address.objectSubId = attnum;

    *relp = relation;
    return address;
}

/*
 * Find the ObjectAddress for an attribute's default value.
 */
static ObjectAddress
get_object_address_attrdef(ObjectType objtype, List *object,
                           Relation *relp, LOCKMODE lockmode,
                           bool missing_ok)
{
    ObjectAddress address;
    List       *relname;
    Oid         reloid;
    Relation    relation;
    const char *attname;
    AttrNumber  attnum;
    TupleDesc   tupdesc;
    Oid         defoid;

    /* Extract relation name and open relation. */
    if (list_length(object) < 2)
        ereport(ERROR,
                (errcode(ERRCODE_SYNTAX_ERROR),
                 errmsg("column name must be qualified")));
    attname = strVal(llast(object));
    relname = list_truncate(list_copy(object), list_length(object) - 1);
    /* XXX no missing_ok support here */
    relation = relation_openrv(makeRangeVarFromNameList(relname), lockmode);
    reloid = RelationGetRelid(relation);

    tupdesc = RelationGetDescr(relation);

    /* Look up attribute number and scan pg_attrdef to find its tuple */
    attnum = get_attnum(reloid, attname);
    defoid = InvalidOid;
    if (attnum != InvalidAttrNumber && tupdesc->constr != NULL)
    {
        Relation    attrdef;
        ScanKeyData keys[2];
        SysScanDesc scan;
        HeapTuple   tup;

        attrdef = relation_open(AttrDefaultRelationId, AccessShareLock);
        ScanKeyInit(&keys[0],
                    Anum_pg_attrdef_adrelid,
                    BTEqualStrategyNumber,
                    F_OIDEQ,
                    ObjectIdGetDatum(reloid));
        ScanKeyInit(&keys[1],
                    Anum_pg_attrdef_adnum,
                    BTEqualStrategyNumber,
                    F_INT2EQ,
                    Int16GetDatum(attnum));
        scan = systable_beginscan(attrdef, AttrDefaultIndexId, true,
                                  NULL, 2, keys);
        if (HeapTupleIsValid(tup = systable_getnext(scan)))
        {
            Form_pg_attrdef atdform = (Form_pg_attrdef) GETSTRUCT(tup);

            defoid = atdform->oid;
        }

        systable_endscan(scan);
        relation_close(attrdef, AccessShareLock);
    }
    if (!OidIsValid(defoid))
    {
        if (!missing_ok)
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_COLUMN),
                     errmsg("default value for column \"%s\" of relation \"%s\" does not exist",
                            attname, NameListToString(relname))));

        address.classId = AttrDefaultRelationId;
        address.objectId = InvalidOid;
        address.objectSubId = InvalidAttrNumber;
        relation_close(relation, lockmode);
        return address;
    }

    address.classId = AttrDefaultRelationId;
    address.objectId = defoid;
    address.objectSubId = 0;

    *relp = relation;
    return address;
}

/*
 * Find the ObjectAddress for a type or domain
 */
static ObjectAddress
get_object_address_type(ObjectType objtype, TypeName *typename, bool missing_ok)
{
    ObjectAddress address;
    Type        tup;

    address.classId = TypeRelationId;
    address.objectId = InvalidOid;
    address.objectSubId = 0;

    tup = LookupTypeName(NULL, typename, NULL, missing_ok);
    if (!HeapTupleIsValid(tup))
    {
        if (!missing_ok)
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_OBJECT),
                     errmsg("type \"%s\" does not exist",
                            TypeNameToString(typename))));
        return address;
    }
    address.objectId = typeTypeId(tup);

    if (objtype == OBJECT_DOMAIN)
    {
        if (((Form_pg_type) GETSTRUCT(tup))->typtype != TYPTYPE_DOMAIN)
            ereport(ERROR,
                    (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                     errmsg("\"%s\" is not a domain",
                            TypeNameToString(typename))));
    }

    ReleaseSysCache(tup);

    return address;
}

/*
 * Find the ObjectAddress for an opclass or opfamily.
 */
static ObjectAddress
get_object_address_opcf(ObjectType objtype, List *object, bool missing_ok)
{
    Oid         amoid;
    ObjectAddress address;

    /* XXX no missing_ok support here */
    amoid = get_index_am_oid(strVal(linitial(object)), false);
    object = list_copy_tail(object, 1);

    switch (objtype)
    {
        case OBJECT_OPCLASS:
            address.classId = OperatorClassRelationId;
            address.objectId = get_opclass_oid(amoid, object, missing_ok);
            address.objectSubId = 0;
            break;
        case OBJECT_OPFAMILY:
            address.classId = OperatorFamilyRelationId;
            address.objectId = get_opfamily_oid(amoid, object, missing_ok);
            address.objectSubId = 0;
            break;
        default:
            elog(ERROR, "unrecognized objtype: %d", (int) objtype);
            /* placate compiler, which doesn't know elog won't return */
            address.classId = InvalidOid;
            address.objectId = InvalidOid;
            address.objectSubId = 0;
    }

    return address;
}

/*
 * Find the ObjectAddress for an opclass/opfamily member.
 *
 * (The returned address corresponds to a pg_amop/pg_amproc object).
 */
static ObjectAddress
get_object_address_opf_member(ObjectType objtype,
                              List *object, bool missing_ok)
{
    ObjectAddress famaddr;
    ObjectAddress address;
    ListCell   *cell;
    List       *copy;
    TypeName   *typenames[2];
    Oid         typeoids[2];
    int         membernum;
    int         i;

    /*
     * The last element of the object list contains the strategy or procedure
     * number.  We need to strip that out before getting the opclass/family
     * address.  The rest can be used directly by get_object_address_opcf().
     */
    membernum = atoi(strVal(llast(linitial(object))));
    copy = list_truncate(list_copy(linitial(object)), list_length(linitial(object)) - 1);

    /* no missing_ok support here */
    famaddr = get_object_address_opcf(OBJECT_OPFAMILY, copy, false);

    /* find out left/right type names and OIDs */
    typenames[0] = typenames[1] = NULL;
    typeoids[0] = typeoids[1] = InvalidOid;
    i = 0;
    foreach(cell, lsecond(object))
    {
        ObjectAddress typaddr;

        typenames[i] = lfirst_node(TypeName, cell);
        typaddr = get_object_address_type(OBJECT_TYPE, typenames[i], missing_ok);
        typeoids[i] = typaddr.objectId;
        if (++i >= 2)
            break;
    }

    switch (objtype)
    {
        case OBJECT_AMOP:
            {
                HeapTuple   tp;

                ObjectAddressSet(address, AccessMethodOperatorRelationId,
                                 InvalidOid);

                tp = SearchSysCache4(AMOPSTRATEGY,
                                     ObjectIdGetDatum(famaddr.objectId),
                                     ObjectIdGetDatum(typeoids[0]),
                                     ObjectIdGetDatum(typeoids[1]),
                                     Int16GetDatum(membernum));
                if (!HeapTupleIsValid(tp))
                {
                    if (!missing_ok)
                        ereport(ERROR,
                                (errcode(ERRCODE_UNDEFINED_OBJECT),
                                 errmsg("operator %d (%s, %s) of %s does not exist",
                                        membernum,
                                        TypeNameToString(typenames[0]),
                                        TypeNameToString(typenames[1]),
                                        getObjectDescription(&famaddr))));
                }
                else
                {
                    address.objectId = ((Form_pg_amop) GETSTRUCT(tp))->oid;
                    ReleaseSysCache(tp);
                }
            }
            break;

        case OBJECT_AMPROC:
            {
                HeapTuple   tp;

                ObjectAddressSet(address, AccessMethodProcedureRelationId,
                                 InvalidOid);

                tp = SearchSysCache4(AMPROCNUM,
                                     ObjectIdGetDatum(famaddr.objectId),
                                     ObjectIdGetDatum(typeoids[0]),
                                     ObjectIdGetDatum(typeoids[1]),
                                     Int16GetDatum(membernum));
                if (!HeapTupleIsValid(tp))
                {
                    if (!missing_ok)
                        ereport(ERROR,
                                (errcode(ERRCODE_UNDEFINED_OBJECT),
                                 errmsg("function %d (%s, %s) of %s does not exist",
                                        membernum,
                                        TypeNameToString(typenames[0]),
                                        TypeNameToString(typenames[1]),
                                        getObjectDescription(&famaddr))));
                }
                else
                {
                    address.objectId = ((Form_pg_amproc) GETSTRUCT(tp))->oid;
                    ReleaseSysCache(tp);
                }
            }
            break;
        default:
            elog(ERROR, "unrecognized objtype: %d", (int) objtype);
    }

    return address;
}

/*
 * Find the ObjectAddress for a user mapping.
 */
static ObjectAddress
get_object_address_usermapping(List *object, bool missing_ok)
{
    ObjectAddress address;
    Oid         userid;
    char       *username;
    char       *servername;
    ForeignServer *server;
    HeapTuple   tp;

    ObjectAddressSet(address, UserMappingRelationId, InvalidOid);

    /* fetch string names from input lists, for error messages */
    username = strVal(linitial(object));
    servername = strVal(lsecond(object));

    /* look up pg_authid OID of mapped user; InvalidOid if PUBLIC */
    if (strcmp(username, "public") == 0)
        userid = InvalidOid;
    else
    {
        tp = SearchSysCache1(AUTHNAME,
                             CStringGetDatum(username));
        if (!HeapTupleIsValid(tp))
        {
            if (!missing_ok)
                ereport(ERROR,
                        (errcode(ERRCODE_UNDEFINED_OBJECT),
                         errmsg("user mapping for user \"%s\" on server \"%s\" does not exist",
                                username, servername)));
            return address;
        }
        userid = ((Form_pg_authid) GETSTRUCT(tp))->oid;
        ReleaseSysCache(tp);
    }

    /* Now look up the pg_user_mapping tuple */
    server = GetForeignServerByName(servername, true);
    if (!server)
    {
        if (!missing_ok)
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_OBJECT),
                     errmsg("server \"%s\" does not exist", servername)));
        return address;
    }
    tp = SearchSysCache2(USERMAPPINGUSERSERVER,
                         ObjectIdGetDatum(userid),
                         ObjectIdGetDatum(server->serverid));
    if (!HeapTupleIsValid(tp))
    {
        if (!missing_ok)
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_OBJECT),
                     errmsg("user mapping for user \"%s\" on server \"%s\" does not exist",
                            username, servername)));
        return address;
    }

    address.objectId = ((Form_pg_user_mapping) GETSTRUCT(tp))->oid;

    ReleaseSysCache(tp);

    return address;
}

/*
 * Find the ObjectAddress for a publication relation.  The first element of
 * the object parameter is the relation name, the second is the
 * publication name.
 */
static ObjectAddress
get_object_address_publication_rel(List *object,
                                   Relation *relp, bool missing_ok)
{
    ObjectAddress address;
    Relation    relation;
    List       *relname;
    char       *pubname;
    Publication *pub;

    ObjectAddressSet(address, PublicationRelRelationId, InvalidOid);

    relname = linitial(object);
    relation = relation_openrv_extended(makeRangeVarFromNameList(relname),
                                        AccessShareLock, missing_ok);
    if (!relation)
        return address;

    /* fetch publication name from input list */
    pubname = strVal(lsecond(object));

    /* Now look up the pg_publication tuple */
    pub = GetPublicationByName(pubname, missing_ok);
    if (!pub)
    {
        relation_close(relation, AccessShareLock);
        return address;
    }

    /* Find the publication relation mapping in syscache. */
    address.objectId =
        GetSysCacheOid2(PUBLICATIONRELMAP, Anum_pg_publication_rel_oid,
                        ObjectIdGetDatum(RelationGetRelid(relation)),
                        ObjectIdGetDatum(pub->oid));
    if (!OidIsValid(address.objectId))
    {
        if (!missing_ok)
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_OBJECT),
                     errmsg("publication relation \"%s\" in publication \"%s\" does not exist",
                            RelationGetRelationName(relation), pubname)));
        relation_close(relation, AccessShareLock);
        return address;
    }

    *relp = relation;
    return address;
}

/*
 * Find the ObjectAddress for a default ACL.
 */
static ObjectAddress
get_object_address_defacl(List *object, bool missing_ok)
{
    HeapTuple   tp;
    Oid         userid;
    Oid         schemaid;
    char       *username;
    char       *schema;
    char        objtype;
    char       *objtype_str;
    ObjectAddress address;

    ObjectAddressSet(address, DefaultAclRelationId, InvalidOid);

    /*
     * First figure out the textual attributes so that they can be used for
     * error reporting.
     */
    username = strVal(lsecond(object));
    if (list_length(object) >= 3)
        schema = (char *) strVal(lthird(object));
    else
        schema = NULL;

    /*
     * Decode defaclobjtype.  Only first char is considered; the rest of the
     * string, if any, is blissfully ignored.
     */
    objtype = ((char *) strVal(linitial(object)))[0];
    switch (objtype)
    {
        case DEFACLOBJ_RELATION:
            objtype_str = "tables";
            break;
        case DEFACLOBJ_SEQUENCE:
            objtype_str = "sequences";
            break;
        case DEFACLOBJ_FUNCTION:
            objtype_str = "functions";
            break;
        case DEFACLOBJ_TYPE:
            objtype_str = "types";
            break;
        case DEFACLOBJ_NAMESPACE:
            objtype_str = "schemas";
            break;
        default:
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("unrecognized default ACL object type \"%c\"", objtype),
                     errhint("Valid object types are \"%c\", \"%c\", \"%c\", \"%c\", \"%c\".",
                             DEFACLOBJ_RELATION,
                             DEFACLOBJ_SEQUENCE,
                             DEFACLOBJ_FUNCTION,
                             DEFACLOBJ_TYPE,
                             DEFACLOBJ_NAMESPACE)));
    }

    /*
     * Look up user ID.  Behave as "default ACL not found" if the user doesn't
     * exist.
     */
    tp = SearchSysCache1(AUTHNAME,
                         CStringGetDatum(username));
    if (!HeapTupleIsValid(tp))
        goto not_found;
    userid = ((Form_pg_authid) GETSTRUCT(tp))->oid;
    ReleaseSysCache(tp);

    /*
     * If a schema name was given, look up its OID.  If it doesn't exist,
     * behave as "default ACL not found".
     */
    if (schema)
    {
        schemaid = get_namespace_oid(schema, true);
        if (schemaid == InvalidOid)
            goto not_found;
    }
    else
        schemaid = InvalidOid;

    /* Finally, look up the pg_default_acl object */
    tp = SearchSysCache3(DEFACLROLENSPOBJ,
                         ObjectIdGetDatum(userid),
                         ObjectIdGetDatum(schemaid),
                         CharGetDatum(objtype));
    if (!HeapTupleIsValid(tp))
        goto not_found;

    address.objectId = ((Form_pg_default_acl) GETSTRUCT(tp))->oid;
    ReleaseSysCache(tp);

    return address;

not_found:
    if (!missing_ok)
    {
        if (schema)
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_OBJECT),
                     errmsg("default ACL for user \"%s\" in schema \"%s\" on %s does not exist",
                            username, schema, objtype_str)));
        else
            ereport(ERROR,
                    (errcode(ERRCODE_UNDEFINED_OBJECT),
                     errmsg("default ACL for user \"%s\" on %s does not exist",
                            username, objtype_str)));
    }
    return address;
}

/*
 * Convert an array of TEXT into a List of string Values, as emitted by the
 * parser, which is what get_object_address uses as input.
 */
static List *
textarray_to_strvaluelist(ArrayType *arr)
{
    Datum      *elems;
    bool       *nulls;
    int         nelems;
    List       *list = NIL;
    int         i;

    deconstruct_array(arr, TEXTOID, -1, false, 'i',
                      &elems, &nulls, &nelems);

    for (i = 0; i < nelems; i++)
    {
        if (nulls[i])
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("name or argument lists may not contain nulls")));
        list = lappend(list, makeString(TextDatumGetCString(elems[i])));
    }

    return list;
}

/*
 * SQL-callable version of get_object_address
 */
Datum
pg_get_object_address(PG_FUNCTION_ARGS)
{
    char       *ttype = TextDatumGetCString(PG_GETARG_DATUM(0));
    ArrayType  *namearr = PG_GETARG_ARRAYTYPE_P(1);
    ArrayType  *argsarr = PG_GETARG_ARRAYTYPE_P(2);
    int         itype;
    ObjectType  type;
    List       *name = NIL;
    TypeName   *typename = NULL;
    List       *args = NIL;
    Node       *objnode = NULL;
    ObjectAddress addr;
    TupleDesc   tupdesc;
    Datum       values[3];
    bool        nulls[3];
    HeapTuple   htup;
    Relation    relation;

    /* Decode object type, raise error if unknown */
    itype = read_objtype_from_string(ttype);
    if (itype < 0)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                 errmsg("unsupported object type \"%s\"", ttype)));
    type = (ObjectType) itype;

    /*
     * Convert the text array to the representation appropriate for the given
     * object type.  Most use a simple string Values list, but there are some
     * exceptions.
     */
    if (type == OBJECT_TYPE || type == OBJECT_DOMAIN || type == OBJECT_CAST ||
        type == OBJECT_TRANSFORM || type == OBJECT_DOMCONSTRAINT)
    {
        Datum      *elems;
        bool       *nulls;
        int         nelems;

        deconstruct_array(namearr, TEXTOID, -1, false, 'i',
                          &elems, &nulls, &nelems);
        if (nelems != 1)
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("name list length must be exactly %d", 1)));
        if (nulls[0])
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("name or argument lists may not contain nulls")));
        typename = typeStringToTypeName(TextDatumGetCString(elems[0]));
    }
    else if (type == OBJECT_LARGEOBJECT)
    {
        Datum      *elems;
        bool       *nulls;
        int         nelems;

        deconstruct_array(namearr, TEXTOID, -1, false, 'i',
                          &elems, &nulls, &nelems);
        if (nelems != 1)
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("name list length must be exactly %d", 1)));
        if (nulls[0])
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("large object OID may not be null")));
        objnode = (Node *) makeFloat(TextDatumGetCString(elems[0]));
    }
    else
    {
        name = textarray_to_strvaluelist(namearr);
        if (list_length(name) < 1)
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("name list length must be at least %d", 1)));
    }

    /*
     * If args are given, decode them according to the object type.
     */
    if (type == OBJECT_AGGREGATE ||
        type == OBJECT_FUNCTION ||
        type == OBJECT_PROCEDURE ||
        type == OBJECT_ROUTINE ||
        type == OBJECT_OPERATOR ||
        type == OBJECT_CAST ||
        type == OBJECT_AMOP ||
        type == OBJECT_AMPROC)
    {
        /* in these cases, the args list must be of TypeName */
        Datum      *elems;
        bool       *nulls;
        int         nelems;
        int         i;

        deconstruct_array(argsarr, TEXTOID, -1, false, 'i',
                          &elems, &nulls, &nelems);

        args = NIL;
        for (i = 0; i < nelems; i++)
        {
            if (nulls[i])
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("name or argument lists may not contain nulls")));
            args = lappend(args,
                           typeStringToTypeName(TextDatumGetCString(elems[i])));
        }
    }
    else
    {
        /* For all other object types, use string Values */
        args = textarray_to_strvaluelist(argsarr);
    }

    /*
     * get_object_address is pretty sensitive to the length of its input
     * lists; check that they're what it wants.
     */
    switch (type)
    {
        case OBJECT_DOMCONSTRAINT:
        case OBJECT_CAST:
        case OBJECT_USER_MAPPING:
        case OBJECT_PUBLICATION_REL:
        case OBJECT_DEFACL:
        case OBJECT_TRANSFORM:
            if (list_length(args) != 1)
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("argument list length must be exactly %d", 1)));
            break;
        case OBJECT_OPFAMILY:
        case OBJECT_OPCLASS:
            if (list_length(name) < 2)
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("name list length must be at least %d", 2)));
            break;
        case OBJECT_AMOP:
        case OBJECT_AMPROC:
            if (list_length(name) < 3)
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("name list length must be at least %d", 3)));
            /* fall through to check args length */
            /* FALLTHROUGH */
        case OBJECT_OPERATOR:
            if (list_length(args) != 2)
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("argument list length must be exactly %d", 2)));
            break;
        default:
            break;
    }

    /*
     * Now build the Node type that get_object_address() expects for the given
     * type.
     */
    switch (type)
    {
        case OBJECT_TABLE:
        case OBJECT_SEQUENCE:
        case OBJECT_VIEW:
        case OBJECT_MATVIEW:
        case OBJECT_INDEX:
        case OBJECT_FOREIGN_TABLE:
        case OBJECT_COLUMN:
        case OBJECT_ATTRIBUTE:
        case OBJECT_COLLATION:
        case OBJECT_CONVERSION:
        case OBJECT_STATISTIC_EXT:
        case OBJECT_TSPARSER:
        case OBJECT_TSDICTIONARY:
        case OBJECT_TSTEMPLATE:
        case OBJECT_TSCONFIGURATION:
        case OBJECT_DEFAULT:
        case OBJECT_POLICY:
        case OBJECT_RULE:
        case OBJECT_TRIGGER:
        case OBJECT_TABCONSTRAINT:
        case OBJECT_OPCLASS:
        case OBJECT_OPFAMILY:
            objnode = (Node *) name;
            break;
        case OBJECT_ACCESS_METHOD:
        case OBJECT_DATABASE:
        case OBJECT_EVENT_TRIGGER:
        case OBJECT_EXTENSION:
        case OBJECT_FDW:
        case OBJECT_FOREIGN_SERVER:
        case OBJECT_LANGUAGE:
        case OBJECT_PUBLICATION:
        case OBJECT_ROLE:
        case OBJECT_SCHEMA:
        case OBJECT_SUBSCRIPTION:
        case OBJECT_TABLESPACE:
            if (list_length(name) != 1)
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("name list length must be exactly %d", 1)));
            objnode = linitial(name);
            break;
        case OBJECT_TYPE:
        case OBJECT_DOMAIN:
            objnode = (Node *) typename;
            break;
        case OBJECT_CAST:
        case OBJECT_DOMCONSTRAINT:
        case OBJECT_TRANSFORM:
            objnode = (Node *) list_make2(typename, linitial(args));
            break;
        case OBJECT_PUBLICATION_REL:
            objnode = (Node *) list_make2(name, linitial(args));
            break;
        case OBJECT_USER_MAPPING:
            objnode = (Node *) list_make2(linitial(name), linitial(args));
            break;
        case OBJECT_DEFACL:
            objnode = (Node *) lcons(linitial(args), name);
            break;
        case OBJECT_AMOP:
        case OBJECT_AMPROC:
            objnode = (Node *) list_make2(name, args);
            break;
        case OBJECT_FUNCTION:
        case OBJECT_PROCEDURE:
        case OBJECT_ROUTINE:
        case OBJECT_AGGREGATE:
        case OBJECT_OPERATOR:
            {
                ObjectWithArgs *owa = makeNode(ObjectWithArgs);

                owa->objname = name;
                owa->objargs = args;
                objnode = (Node *) owa;
                break;
            }
        case OBJECT_LARGEOBJECT:
            /* already handled above */
            break;
            /* no default, to let compiler warn about missing case */
    }

    if (objnode == NULL)
        elog(ERROR, "unrecognized object type: %d", type);

    addr = get_object_address(type, objnode,
                              &relation, AccessShareLock, false);

    /* We don't need the relcache entry, thank you very much */
    if (relation)
        relation_close(relation, AccessShareLock);

    tupdesc = CreateTemplateTupleDesc(3);
    TupleDescInitEntry(tupdesc, (AttrNumber) 1, "classid",
                       OIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 2, "objid",
                       OIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 3, "objsubid",
                       INT4OID, -1, 0);
    tupdesc = BlessTupleDesc(tupdesc);

    values[0] = ObjectIdGetDatum(addr.classId);
    values[1] = ObjectIdGetDatum(addr.objectId);
    values[2] = Int32GetDatum(addr.objectSubId);
    nulls[0] = false;
    nulls[1] = false;
    nulls[2] = false;

    htup = heap_form_tuple(tupdesc, values, nulls);

    PG_RETURN_DATUM(HeapTupleGetDatum(htup));
}

/*
 * Check ownership of an object previously identified by get_object_address.
 */
void
check_object_ownership(Oid roleid, ObjectType objtype, ObjectAddress address,
                       Node *object, Relation relation)
{
    switch (objtype)
    {
        case OBJECT_INDEX:
        case OBJECT_SEQUENCE:
        case OBJECT_TABLE:
        case OBJECT_VIEW:
        case OBJECT_MATVIEW:
        case OBJECT_FOREIGN_TABLE:
        case OBJECT_COLUMN:
        case OBJECT_RULE:
        case OBJECT_TRIGGER:
        case OBJECT_POLICY:
        case OBJECT_TABCONSTRAINT:
            if (!pg_class_ownercheck(RelationGetRelid(relation), roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               RelationGetRelationName(relation));
            break;
        case OBJECT_DATABASE:
            if (!pg_database_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               strVal((Value *) object));
            break;
        case OBJECT_TYPE:
        case OBJECT_DOMAIN:
        case OBJECT_ATTRIBUTE:
            if (!pg_type_ownercheck(address.objectId, roleid))
                aclcheck_error_type(ACLCHECK_NOT_OWNER, address.objectId);
            break;
        case OBJECT_DOMCONSTRAINT:
            {
                HeapTuple   tuple;
                Oid         contypid;

                tuple = SearchSysCache1(CONSTROID,
                                        ObjectIdGetDatum(address.objectId));
                if (!HeapTupleIsValid(tuple))
                    elog(ERROR, "constraint with OID %u does not exist",
                         address.objectId);

                contypid = ((Form_pg_constraint) GETSTRUCT(tuple))->contypid;

                ReleaseSysCache(tuple);

                /*
                 * Fallback to type ownership check in this case as this is
                 * what domain constraints rely on.
                 */
                if (!pg_type_ownercheck(contypid, roleid))
                    aclcheck_error_type(ACLCHECK_NOT_OWNER, contypid);
            }
            break;
        case OBJECT_AGGREGATE:
        case OBJECT_FUNCTION:
        case OBJECT_PROCEDURE:
        case OBJECT_ROUTINE:
            if (!pg_proc_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               NameListToString((castNode(ObjectWithArgs, object))->objname));
            break;
        case OBJECT_OPERATOR:
            if (!pg_oper_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               NameListToString((castNode(ObjectWithArgs, object))->objname));
            break;
        case OBJECT_SCHEMA:
            if (!pg_namespace_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               strVal((Value *) object));
            break;
        case OBJECT_COLLATION:
            if (!pg_collation_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               NameListToString(castNode(List, object)));
            break;
        case OBJECT_CONVERSION:
            if (!pg_conversion_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               NameListToString(castNode(List, object)));
            break;
        case OBJECT_EXTENSION:
            if (!pg_extension_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               strVal((Value *) object));
            break;
        case OBJECT_FDW:
            if (!pg_foreign_data_wrapper_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               strVal((Value *) object));
            break;
        case OBJECT_FOREIGN_SERVER:
            if (!pg_foreign_server_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               strVal((Value *) object));
            break;
        case OBJECT_EVENT_TRIGGER:
            if (!pg_event_trigger_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               strVal((Value *) object));
            break;
        case OBJECT_LANGUAGE:
            if (!pg_language_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               strVal((Value *) object));
            break;
        case OBJECT_OPCLASS:
            if (!pg_opclass_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               NameListToString(castNode(List, object)));
            break;
        case OBJECT_OPFAMILY:
            if (!pg_opfamily_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               NameListToString(castNode(List, object)));
            break;
        case OBJECT_LARGEOBJECT:
            if (!lo_compat_privileges &&
                !pg_largeobject_ownercheck(address.objectId, roleid))
                ereport(ERROR,
                        (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                         errmsg("must be owner of large object %u",
                                address.objectId)));
            break;
        case OBJECT_CAST:
            {
                /* We can only check permissions on the source/target types */
                TypeName   *sourcetype = linitial_node(TypeName, castNode(List, object));
                TypeName   *targettype = lsecond_node(TypeName, castNode(List, object));
                Oid         sourcetypeid = typenameTypeId(NULL, sourcetype);
                Oid         targettypeid = typenameTypeId(NULL, targettype);

                if (!pg_type_ownercheck(sourcetypeid, roleid)
                    && !pg_type_ownercheck(targettypeid, roleid))
                    ereport(ERROR,
                            (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                             errmsg("must be owner of type %s or type %s",
                                    format_type_be(sourcetypeid),
                                    format_type_be(targettypeid))));
            }
            break;
        case OBJECT_PUBLICATION:
            if (!pg_publication_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               strVal((Value *) object));
            break;
        case OBJECT_SUBSCRIPTION:
            if (!pg_subscription_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               strVal((Value *) object));
            break;
        case OBJECT_TRANSFORM:
            {
                TypeName   *typename = linitial_node(TypeName, castNode(List, object));
                Oid         typeid = typenameTypeId(NULL, typename);

                if (!pg_type_ownercheck(typeid, roleid))
                    aclcheck_error_type(ACLCHECK_NOT_OWNER, typeid);
            }
            break;
        case OBJECT_TABLESPACE:
            if (!pg_tablespace_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               strVal((Value *) object));
            break;
        case OBJECT_TSDICTIONARY:
            if (!pg_ts_dict_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               NameListToString(castNode(List, object)));
            break;
        case OBJECT_TSCONFIGURATION:
            if (!pg_ts_config_ownercheck(address.objectId, roleid))
                aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
                               NameListToString(castNode(List, object)));
            break;
        case OBJECT_ROLE:

            /*
             * We treat roles as being "owned" by those with CREATEROLE priv,
             * except that superusers are only owned by superusers.
             */
            if (superuser_arg(address.objectId))
            {
                if (!superuser_arg(roleid))
                    ereport(ERROR,
                            (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                             errmsg("must be superuser")));
            }
            else
            {
                if (!has_createrole_privilege(roleid))
                    ereport(ERROR,
                            (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                             errmsg("must have CREATEROLE privilege")));
            }
            break;
        case OBJECT_TSPARSER:
        case OBJECT_TSTEMPLATE:
        case OBJECT_ACCESS_METHOD:
            /* We treat these object types as being owned by superusers */
            if (!superuser_arg(roleid))
                ereport(ERROR,
                        (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                         errmsg("must be superuser")));
            break;
        case OBJECT_STATISTIC_EXT:
            if (!pg_statistics_object_ownercheck(address.objectId, roleid))
                aclcheck_error_type(ACLCHECK_NOT_OWNER, address.objectId);
            break;
        default:
            elog(ERROR, "unrecognized object type: %d",
                 (int) objtype);
    }
}

/*
 * get_object_namespace
 *
 * Find the schema containing the specified object.  For non-schema objects,
 * this function returns InvalidOid.
 */
Oid
get_object_namespace(const ObjectAddress *address)
{
    int         cache;
    HeapTuple   tuple;
    bool        isnull;
    Oid         oid;
    const ObjectPropertyType *property;

    /* If not owned by a namespace, just return InvalidOid. */
    property = get_object_property_data(address->classId);
    if (property->attnum_namespace == InvalidAttrNumber)
        return InvalidOid;

    /* Currently, we can only handle object types with system caches. */
    cache = property->oid_catcache_id;
    Assert(cache != -1);

    /* Fetch tuple from syscache and extract namespace attribute. */
    tuple = SearchSysCache1(cache, ObjectIdGetDatum(address->objectId));
    if (!HeapTupleIsValid(tuple))
        elog(ERROR, "cache lookup failed for cache %d oid %u",
             cache, address->objectId);
    oid = DatumGetObjectId(SysCacheGetAttr(cache,
                                           tuple,
                                           property->attnum_namespace,
                                           &isnull));
    Assert(!isnull);
    ReleaseSysCache(tuple);

    return oid;
}

/*
 * Return ObjectType for the given object type as given by
 * getObjectTypeDescription; if no valid ObjectType code exists, but it's a
 * possible output type from getObjectTypeDescription, return -1.
 * Otherwise, an error is thrown.
 */
int
read_objtype_from_string(const char *objtype)
{
    int         i;

    for (i = 0; i < lengthof(ObjectTypeMap); i++)
    {
        if (strcmp(ObjectTypeMap[i].tm_name, objtype) == 0)
            return ObjectTypeMap[i].tm_type;
    }
    ereport(ERROR,
            (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
             errmsg("unrecognized object type \"%s\"", objtype)));

    return -1;                  /* keep compiler quiet */
}

/*
 * Interfaces to reference fields of ObjectPropertyType
 */
Oid
get_object_oid_index(Oid class_id)
{
    const ObjectPropertyType *prop = get_object_property_data(class_id);

    return prop->oid_index_oid;
}

int
get_object_catcache_oid(Oid class_id)
{
    const ObjectPropertyType *prop = get_object_property_data(class_id);

    return prop->oid_catcache_id;
}

int
get_object_catcache_name(Oid class_id)
{
    const ObjectPropertyType *prop = get_object_property_data(class_id);

    return prop->name_catcache_id;
}

AttrNumber
get_object_attnum_oid(Oid class_id)
{
    const ObjectPropertyType *prop = get_object_property_data(class_id);

    return prop->attnum_oid;
}

AttrNumber
get_object_attnum_name(Oid class_id)
{
    const ObjectPropertyType *prop = get_object_property_data(class_id);

    return prop->attnum_name;
}

AttrNumber
get_object_attnum_namespace(Oid class_id)
{
    const ObjectPropertyType *prop = get_object_property_data(class_id);

    return prop->attnum_namespace;
}

AttrNumber
get_object_attnum_owner(Oid class_id)
{
    const ObjectPropertyType *prop = get_object_property_data(class_id);

    return prop->attnum_owner;
}

AttrNumber
get_object_attnum_acl(Oid class_id)
{
    const ObjectPropertyType *prop = get_object_property_data(class_id);

    return prop->attnum_acl;
}

/*
 * get_object_type
 *
 * Return the object type associated with a given object.  This routine
 * is primarily used to determine the object type to mention in ACL check
 * error messages, so it's desirable for it to avoid failing.
 */
ObjectType
get_object_type(Oid class_id, Oid object_id)
{
    const ObjectPropertyType *prop = get_object_property_data(class_id);

    if (prop->objtype == OBJECT_TABLE)
    {
        /*
         * If the property data says it's a table, dig a little deeper to get
         * the real relation kind, so that callers can produce more precise
         * error messages.
         */
        return get_relkind_objtype(get_rel_relkind(object_id));
    }
    else
        return prop->objtype;
}

bool
get_object_namensp_unique(Oid class_id)
{
    const ObjectPropertyType *prop = get_object_property_data(class_id);

    return prop->is_nsp_name_unique;
}

/*
 * Return whether we have useful data for the given object class in the
 * ObjectProperty table.
 */
bool
is_objectclass_supported(Oid class_id)
{
    int         index;

    for (index = 0; index < lengthof(ObjectProperty); index++)
    {
        if (ObjectProperty[index].class_oid == class_id)
            return true;
    }

    return false;
}

/*
 * Find ObjectProperty structure by class_id.
 */
static const ObjectPropertyType *
get_object_property_data(Oid class_id)
{
    static const ObjectPropertyType *prop_last = NULL;
    int         index;

    /*
     * A shortcut to speed up multiple consecutive lookups of a particular
     * object class.
     */
    if (prop_last && prop_last->class_oid == class_id)
        return prop_last;

    for (index = 0; index < lengthof(ObjectProperty); index++)
    {
        if (ObjectProperty[index].class_oid == class_id)
        {
            prop_last = &ObjectProperty[index];
            return &ObjectProperty[index];
        }
    }

    ereport(ERROR,
            (errmsg_internal("unrecognized class ID: %u", class_id)));

    return NULL;                /* keep MSC compiler happy */
}

/*
 * Return a copy of the tuple for the object with the given object OID, from
 * the given catalog (which must have been opened by the caller and suitably
 * locked).  NULL is returned if the OID is not found.
 *
 * We try a syscache first, if available.
 */
HeapTuple
get_catalog_object_by_oid(Relation catalog, AttrNumber oidcol, Oid objectId)
{
    HeapTuple   tuple;
    Oid         classId = RelationGetRelid(catalog);
    int         oidCacheId = get_object_catcache_oid(classId);

    if (oidCacheId > 0)
    {
        tuple = SearchSysCacheCopy1(oidCacheId, ObjectIdGetDatum(objectId));
        if (!HeapTupleIsValid(tuple))   /* should not happen */
            return NULL;
    }
    else
    {
        Oid         oidIndexId = get_object_oid_index(classId);
        SysScanDesc scan;
        ScanKeyData skey;

        Assert(OidIsValid(oidIndexId));

        ScanKeyInit(&skey,
                    oidcol,
                    BTEqualStrategyNumber, F_OIDEQ,
                    ObjectIdGetDatum(objectId));

        scan = systable_beginscan(catalog, oidIndexId, true,
                                  NULL, 1, &skey);
        tuple = systable_getnext(scan);
        if (!HeapTupleIsValid(tuple))
        {
            systable_endscan(scan);
            return NULL;
        }
        tuple = heap_copytuple(tuple);

        systable_endscan(scan);
    }

    return tuple;
}

/*
 * getObjectDescription: build an object description for messages
 *
 * The result is a palloc'd string.
 */
char *
getObjectDescription(const ObjectAddress *object)
{
    StringInfoData buffer;

    initStringInfo(&buffer);

    switch (getObjectClass(object))
    {
        case OCLASS_CLASS:
            if (object->objectSubId == 0)
                getRelationDescription(&buffer, object->objectId);
            else
            {
                /* column, not whole relation */
                StringInfoData rel;

                initStringInfo(&rel);
                getRelationDescription(&rel, object->objectId);
                /* translator: second %s is, e.g., "table %s" */
                appendStringInfo(&buffer, _("column %s of %s"),
                                 get_attname(object->objectId,
                                             object->objectSubId,
                                             false),
                                 rel.data);
                pfree(rel.data);
            }
            break;

        case OCLASS_PROC:
            appendStringInfo(&buffer, _("function %s"),
                             format_procedure(object->objectId));
            break;

        case OCLASS_TYPE:
            appendStringInfo(&buffer, _("type %s"),
                             format_type_be(object->objectId));
            break;

        case OCLASS_CAST:
            {
                Relation    castDesc;
                ScanKeyData skey[1];
                SysScanDesc rcscan;
                HeapTuple   tup;
                Form_pg_cast castForm;

                castDesc = table_open(CastRelationId, AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_cast_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                rcscan = systable_beginscan(castDesc, CastOidIndexId, true,
                                            NULL, 1, skey);

                tup = systable_getnext(rcscan);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for cast %u",
                         object->objectId);

                castForm = (Form_pg_cast) GETSTRUCT(tup);

                appendStringInfo(&buffer, _("cast from %s to %s"),
                                 format_type_be(castForm->castsource),
                                 format_type_be(castForm->casttarget));

                systable_endscan(rcscan);
                table_close(castDesc, AccessShareLock);
                break;
            }

        case OCLASS_COLLATION:
            {
                HeapTuple   collTup;
                Form_pg_collation coll;
                char       *nspname;

                collTup = SearchSysCache1(COLLOID,
                                          ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(collTup))
                    elog(ERROR, "cache lookup failed for collation %u",
                         object->objectId);
                coll = (Form_pg_collation) GETSTRUCT(collTup);

                /* Qualify the name if not visible in search path */
                if (CollationIsVisible(object->objectId))
                    nspname = NULL;
                else
                    nspname = get_namespace_name(coll->collnamespace);

                appendStringInfo(&buffer, _("collation %s"),
                                 quote_qualified_identifier(nspname,
                                                            NameStr(coll->collname)));
                ReleaseSysCache(collTup);
                break;
            }

        case OCLASS_CONSTRAINT:
            {
                HeapTuple   conTup;
                Form_pg_constraint con;

                conTup = SearchSysCache1(CONSTROID,
                                         ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(conTup))
                    elog(ERROR, "cache lookup failed for constraint %u",
                         object->objectId);
                con = (Form_pg_constraint) GETSTRUCT(conTup);

                if (OidIsValid(con->conrelid))
                {
                    StringInfoData rel;

                    initStringInfo(&rel);
                    getRelationDescription(&rel, con->conrelid);
                    /* translator: second %s is, e.g., "table %s" */
                    appendStringInfo(&buffer, _("constraint %s on %s"),
                                     NameStr(con->conname), rel.data);
                    pfree(rel.data);
                }
                else
                {
                    appendStringInfo(&buffer, _("constraint %s"),
                                     NameStr(con->conname));
                }

                ReleaseSysCache(conTup);
                break;
            }

        case OCLASS_CONVERSION:
            {
                HeapTuple   conTup;
                Form_pg_conversion conv;
                char       *nspname;

                conTup = SearchSysCache1(CONVOID,
                                         ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(conTup))
                    elog(ERROR, "cache lookup failed for conversion %u",
                         object->objectId);
                conv = (Form_pg_conversion) GETSTRUCT(conTup);

                /* Qualify the name if not visible in search path */
                if (ConversionIsVisible(object->objectId))
                    nspname = NULL;
                else
                    nspname = get_namespace_name(conv->connamespace);

                appendStringInfo(&buffer, _("conversion %s"),
                                 quote_qualified_identifier(nspname,
                                                            NameStr(conv->conname)));
                ReleaseSysCache(conTup);
                break;
            }

        case OCLASS_DEFAULT:
            {
                Relation    attrdefDesc;
                ScanKeyData skey[1];
                SysScanDesc adscan;
                HeapTuple   tup;
                Form_pg_attrdef attrdef;
                ObjectAddress colobject;

                attrdefDesc = table_open(AttrDefaultRelationId, AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_attrdef_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                adscan = systable_beginscan(attrdefDesc, AttrDefaultOidIndexId,
                                            true, NULL, 1, skey);

                tup = systable_getnext(adscan);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for attrdef %u",
                         object->objectId);

                attrdef = (Form_pg_attrdef) GETSTRUCT(tup);

                colobject.classId = RelationRelationId;
                colobject.objectId = attrdef->adrelid;
                colobject.objectSubId = attrdef->adnum;

                /* translator: %s is typically "column %s of table %s" */
                appendStringInfo(&buffer, _("default value for %s"),
                                 getObjectDescription(&colobject));

                systable_endscan(adscan);
                table_close(attrdefDesc, AccessShareLock);
                break;
            }

        case OCLASS_LANGUAGE:
            appendStringInfo(&buffer, _("language %s"),
                             get_language_name(object->objectId, false));
            break;

        case OCLASS_LARGEOBJECT:
            appendStringInfo(&buffer, _("large object %u"),
                             object->objectId);
            break;

        case OCLASS_OPERATOR:
            appendStringInfo(&buffer, _("operator %s"),
                             format_operator(object->objectId));
            break;

        case OCLASS_OPCLASS:
            {
                HeapTuple   opcTup;
                Form_pg_opclass opcForm;
                HeapTuple   amTup;
                Form_pg_am  amForm;
                char       *nspname;

                opcTup = SearchSysCache1(CLAOID,
                                         ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(opcTup))
                    elog(ERROR, "cache lookup failed for opclass %u",
                         object->objectId);
                opcForm = (Form_pg_opclass) GETSTRUCT(opcTup);

                amTup = SearchSysCache1(AMOID,
                                        ObjectIdGetDatum(opcForm->opcmethod));
                if (!HeapTupleIsValid(amTup))
                    elog(ERROR, "cache lookup failed for access method %u",
                         opcForm->opcmethod);
                amForm = (Form_pg_am) GETSTRUCT(amTup);

                /* Qualify the name if not visible in search path */
                if (OpclassIsVisible(object->objectId))
                    nspname = NULL;
                else
                    nspname = get_namespace_name(opcForm->opcnamespace);

                appendStringInfo(&buffer, _("operator class %s for access method %s"),
                                 quote_qualified_identifier(nspname,
                                                            NameStr(opcForm->opcname)),
                                 NameStr(amForm->amname));

                ReleaseSysCache(amTup);
                ReleaseSysCache(opcTup);
                break;
            }

        case OCLASS_OPFAMILY:
            getOpFamilyDescription(&buffer, object->objectId);
            break;

        case OCLASS_AM:
            {
                HeapTuple   tup;

                tup = SearchSysCache1(AMOID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for access method %u",
                         object->objectId);
                appendStringInfo(&buffer, _("access method %s"),
                                 NameStr(((Form_pg_am) GETSTRUCT(tup))->amname));
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_AMOP:
            {
                Relation    amopDesc;
                HeapTuple   tup;
                ScanKeyData skey[1];
                SysScanDesc amscan;
                Form_pg_amop amopForm;
                StringInfoData opfam;

                amopDesc = table_open(AccessMethodOperatorRelationId,
                                      AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_amop_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                amscan = systable_beginscan(amopDesc, AccessMethodOperatorOidIndexId, true,
                                            NULL, 1, skey);

                tup = systable_getnext(amscan);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for amop entry %u",
                         object->objectId);

                amopForm = (Form_pg_amop) GETSTRUCT(tup);

                initStringInfo(&opfam);
                getOpFamilyDescription(&opfam, amopForm->amopfamily);

                /*------
                   translator: %d is the operator strategy (a number), the
                   first two %s's are data type names, the third %s is the
                   description of the operator family, and the last %s is the
                   textual form of the operator with arguments.  */
                appendStringInfo(&buffer, _("operator %d (%s, %s) of %s: %s"),
                                 amopForm->amopstrategy,
                                 format_type_be(amopForm->amoplefttype),
                                 format_type_be(amopForm->amoprighttype),
                                 opfam.data,
                                 format_operator(amopForm->amopopr));

                pfree(opfam.data);

                systable_endscan(amscan);
                table_close(amopDesc, AccessShareLock);
                break;
            }

        case OCLASS_AMPROC:
            {
                Relation    amprocDesc;
                ScanKeyData skey[1];
                SysScanDesc amscan;
                HeapTuple   tup;
                Form_pg_amproc amprocForm;
                StringInfoData opfam;

                amprocDesc = table_open(AccessMethodProcedureRelationId,
                                        AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_amproc_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                amscan = systable_beginscan(amprocDesc, AccessMethodProcedureOidIndexId, true,
                                            NULL, 1, skey);

                tup = systable_getnext(amscan);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for amproc entry %u",
                         object->objectId);

                amprocForm = (Form_pg_amproc) GETSTRUCT(tup);

                initStringInfo(&opfam);
                getOpFamilyDescription(&opfam, amprocForm->amprocfamily);

                /*------
                   translator: %d is the function number, the first two %s's
                   are data type names, the third %s is the description of the
                   operator family, and the last %s is the textual form of the
                   function with arguments.  */
                appendStringInfo(&buffer, _("function %d (%s, %s) of %s: %s"),
                                 amprocForm->amprocnum,
                                 format_type_be(amprocForm->amproclefttype),
                                 format_type_be(amprocForm->amprocrighttype),
                                 opfam.data,
                                 format_procedure(amprocForm->amproc));

                pfree(opfam.data);

                systable_endscan(amscan);
                table_close(amprocDesc, AccessShareLock);
                break;
            }

        case OCLASS_REWRITE:
            {
                Relation    ruleDesc;
                ScanKeyData skey[1];
                SysScanDesc rcscan;
                HeapTuple   tup;
                Form_pg_rewrite rule;
                StringInfoData rel;

                ruleDesc = table_open(RewriteRelationId, AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_rewrite_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                rcscan = systable_beginscan(ruleDesc, RewriteOidIndexId, true,
                                            NULL, 1, skey);

                tup = systable_getnext(rcscan);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for rule %u",
                         object->objectId);
                rule = (Form_pg_rewrite) GETSTRUCT(tup);

                initStringInfo(&rel);
                getRelationDescription(&rel, rule->ev_class);

                /* translator: second %s is, e.g., "table %s" */
                appendStringInfo(&buffer, _("rule %s on %s"),
                                 NameStr(rule->rulename), rel.data);
                pfree(rel.data);
                systable_endscan(rcscan);
                table_close(ruleDesc, AccessShareLock);
                break;
            }

        case OCLASS_TRIGGER:
            {
                Relation    trigDesc;
                ScanKeyData skey[1];
                SysScanDesc tgscan;
                HeapTuple   tup;
                Form_pg_trigger trig;
                StringInfoData rel;

                trigDesc = table_open(TriggerRelationId, AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_trigger_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                tgscan = systable_beginscan(trigDesc, TriggerOidIndexId, true,
                                            NULL, 1, skey);

                tup = systable_getnext(tgscan);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for trigger %u",
                         object->objectId);
                trig = (Form_pg_trigger) GETSTRUCT(tup);

                initStringInfo(&rel);
                getRelationDescription(&rel, trig->tgrelid);

                /* translator: second %s is, e.g., "table %s" */
                appendStringInfo(&buffer, _("trigger %s on %s"),
                                 NameStr(trig->tgname), rel.data);
                pfree(rel.data);
                systable_endscan(tgscan);
                table_close(trigDesc, AccessShareLock);
                break;
            }

        case OCLASS_SCHEMA:
            {
                char       *nspname;

                nspname = get_namespace_name(object->objectId);
                if (!nspname)
                    elog(ERROR, "cache lookup failed for namespace %u",
                         object->objectId);
                appendStringInfo(&buffer, _("schema %s"), nspname);
                break;
            }

        case OCLASS_STATISTIC_EXT:
            {
                HeapTuple   stxTup;
                Form_pg_statistic_ext stxForm;
                char       *nspname;

                stxTup = SearchSysCache1(STATEXTOID,
                                         ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(stxTup))
                    elog(ERROR, "could not find tuple for statistics object %u",
                         object->objectId);
                stxForm = (Form_pg_statistic_ext) GETSTRUCT(stxTup);

                /* Qualify the name if not visible in search path */
                if (StatisticsObjIsVisible(object->objectId))
                    nspname = NULL;
                else
                    nspname = get_namespace_name(stxForm->stxnamespace);

                appendStringInfo(&buffer, _("statistics object %s"),
                                 quote_qualified_identifier(nspname,
                                                            NameStr(stxForm->stxname)));

                ReleaseSysCache(stxTup);
                break;
            }

        case OCLASS_TSPARSER:
            {
                HeapTuple   tup;
                Form_pg_ts_parser prsForm;
                char       *nspname;

                tup = SearchSysCache1(TSPARSEROID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for text search parser %u",
                         object->objectId);
                prsForm = (Form_pg_ts_parser) GETSTRUCT(tup);

                /* Qualify the name if not visible in search path */
                if (TSParserIsVisible(object->objectId))
                    nspname = NULL;
                else
                    nspname = get_namespace_name(prsForm->prsnamespace);

                appendStringInfo(&buffer, _("text search parser %s"),
                                 quote_qualified_identifier(nspname,
                                                            NameStr(prsForm->prsname)));
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_TSDICT:
            {
                HeapTuple   tup;
                Form_pg_ts_dict dictForm;
                char       *nspname;

                tup = SearchSysCache1(TSDICTOID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for text search dictionary %u",
                         object->objectId);
                dictForm = (Form_pg_ts_dict) GETSTRUCT(tup);

                /* Qualify the name if not visible in search path */
                if (TSDictionaryIsVisible(object->objectId))
                    nspname = NULL;
                else
                    nspname = get_namespace_name(dictForm->dictnamespace);

                appendStringInfo(&buffer, _("text search dictionary %s"),
                                 quote_qualified_identifier(nspname,
                                                            NameStr(dictForm->dictname)));
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_TSTEMPLATE:
            {
                HeapTuple   tup;
                Form_pg_ts_template tmplForm;
                char       *nspname;

                tup = SearchSysCache1(TSTEMPLATEOID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for text search template %u",
                         object->objectId);
                tmplForm = (Form_pg_ts_template) GETSTRUCT(tup);

                /* Qualify the name if not visible in search path */
                if (TSTemplateIsVisible(object->objectId))
                    nspname = NULL;
                else
                    nspname = get_namespace_name(tmplForm->tmplnamespace);

                appendStringInfo(&buffer, _("text search template %s"),
                                 quote_qualified_identifier(nspname,
                                                            NameStr(tmplForm->tmplname)));
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_TSCONFIG:
            {
                HeapTuple   tup;
                Form_pg_ts_config cfgForm;
                char       *nspname;

                tup = SearchSysCache1(TSCONFIGOID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for text search configuration %u",
                         object->objectId);
                cfgForm = (Form_pg_ts_config) GETSTRUCT(tup);

                /* Qualify the name if not visible in search path */
                if (TSConfigIsVisible(object->objectId))
                    nspname = NULL;
                else
                    nspname = get_namespace_name(cfgForm->cfgnamespace);

                appendStringInfo(&buffer, _("text search configuration %s"),
                                 quote_qualified_identifier(nspname,
                                                            NameStr(cfgForm->cfgname)));
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_ROLE:
            {
                appendStringInfo(&buffer, _("role %s"),
                                 GetUserNameFromId(object->objectId, false));
                break;
            }

        case OCLASS_DATABASE:
            {
                char       *datname;

                datname = get_database_name(object->objectId);
                if (!datname)
                    elog(ERROR, "cache lookup failed for database %u",
                         object->objectId);
                appendStringInfo(&buffer, _("database %s"), datname);
                break;
            }

        case OCLASS_TBLSPACE:
            {
                char       *tblspace;

                tblspace = get_tablespace_name(object->objectId);
                if (!tblspace)
                    elog(ERROR, "cache lookup failed for tablespace %u",
                         object->objectId);
                appendStringInfo(&buffer, _("tablespace %s"), tblspace);
                break;
            }

        case OCLASS_FDW:
            {
                ForeignDataWrapper *fdw;

                fdw = GetForeignDataWrapper(object->objectId);
                appendStringInfo(&buffer, _("foreign-data wrapper %s"), fdw->fdwname);
                break;
            }

        case OCLASS_FOREIGN_SERVER:
            {
                ForeignServer *srv;

                srv = GetForeignServer(object->objectId);
                appendStringInfo(&buffer, _("server %s"), srv->servername);
                break;
            }

        case OCLASS_USER_MAPPING:
            {
                HeapTuple   tup;
                Oid         useid;
                char       *usename;
                Form_pg_user_mapping umform;
                ForeignServer *srv;

                tup = SearchSysCache1(USERMAPPINGOID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for user mapping %u",
                         object->objectId);
                umform = (Form_pg_user_mapping) GETSTRUCT(tup);
                useid = umform->umuser;
                srv = GetForeignServer(umform->umserver);

                ReleaseSysCache(tup);

                if (OidIsValid(useid))
                    usename = GetUserNameFromId(useid, false);
                else
                    usename = "public";

                appendStringInfo(&buffer, _("user mapping for %s on server %s"), usename,
                                 srv->servername);
                break;
            }

        case OCLASS_DEFACL:
            {
                Relation    defaclrel;
                ScanKeyData skey[1];
                SysScanDesc rcscan;
                HeapTuple   tup;
                Form_pg_default_acl defacl;
                char       *rolename;
                char       *nspname;

                defaclrel = table_open(DefaultAclRelationId, AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_default_acl_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                rcscan = systable_beginscan(defaclrel, DefaultAclOidIndexId,
                                            true, NULL, 1, skey);

                tup = systable_getnext(rcscan);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for default ACL %u",
                         object->objectId);

                defacl = (Form_pg_default_acl) GETSTRUCT(tup);

                rolename = GetUserNameFromId(defacl->defaclrole, false);

                if (OidIsValid(defacl->defaclnamespace))
                    nspname = get_namespace_name(defacl->defaclnamespace);
                else
                    nspname = NULL;

                switch (defacl->defaclobjtype)
                {
                    case DEFACLOBJ_RELATION:
                        if (nspname)
                            appendStringInfo(&buffer,
                                             _("default privileges on new relations belonging to role %s in schema %s"),
                                             rolename, nspname);
                        else
                            appendStringInfo(&buffer,
                                             _("default privileges on new relations belonging to role %s"),
                                             rolename);
                        break;
                    case DEFACLOBJ_SEQUENCE:
                        if (nspname)
                            appendStringInfo(&buffer,
                                             _("default privileges on new sequences belonging to role %s in schema %s"),
                                             rolename, nspname);
                        else
                            appendStringInfo(&buffer,
                                             _("default privileges on new sequences belonging to role %s"),
                                             rolename);
                        break;
                    case DEFACLOBJ_FUNCTION:
                        if (nspname)
                            appendStringInfo(&buffer,
                                             _("default privileges on new functions belonging to role %s in schema %s"),
                                             rolename, nspname);
                        else
                            appendStringInfo(&buffer,
                                             _("default privileges on new functions belonging to role %s"),
                                             rolename);
                        break;
                    case DEFACLOBJ_TYPE:
                        if (nspname)
                            appendStringInfo(&buffer,
                                             _("default privileges on new types belonging to role %s in schema %s"),
                                             rolename, nspname);
                        else
                            appendStringInfo(&buffer,
                                             _("default privileges on new types belonging to role %s"),
                                             rolename);
                        break;
                    case DEFACLOBJ_NAMESPACE:
                        Assert(!nspname);
                        appendStringInfo(&buffer,
                                         _("default privileges on new schemas belonging to role %s"),
                                         rolename);
                        break;
                    default:
                        /* shouldn't get here */
                        if (nspname)
                            appendStringInfo(&buffer,
                                             _("default privileges belonging to role %s in schema %s"),
                                             rolename, nspname);
                        else
                            appendStringInfo(&buffer,
                                             _("default privileges belonging to role %s"),
                                             rolename);
                        break;
                }

                systable_endscan(rcscan);
                table_close(defaclrel, AccessShareLock);
                break;
            }

        case OCLASS_EXTENSION:
            {
                char       *extname;

                extname = get_extension_name(object->objectId);
                if (!extname)
                    elog(ERROR, "cache lookup failed for extension %u",
                         object->objectId);
                appendStringInfo(&buffer, _("extension %s"), extname);
                break;
            }

        case OCLASS_EVENT_TRIGGER:
            {
                HeapTuple   tup;

                tup = SearchSysCache1(EVENTTRIGGEROID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for event trigger %u",
                         object->objectId);
                appendStringInfo(&buffer, _("event trigger %s"),
                                 NameStr(((Form_pg_event_trigger) GETSTRUCT(tup))->evtname));
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_POLICY:
            {
                Relation    policy_rel;
                ScanKeyData skey[1];
                SysScanDesc sscan;
                HeapTuple   tuple;
                Form_pg_policy form_policy;
                StringInfoData rel;

                policy_rel = table_open(PolicyRelationId, AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_policy_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                sscan = systable_beginscan(policy_rel, PolicyOidIndexId,
                                           true, NULL, 1, skey);

                tuple = systable_getnext(sscan);

                if (!HeapTupleIsValid(tuple))
                    elog(ERROR, "could not find tuple for policy %u",
                         object->objectId);
                form_policy = (Form_pg_policy) GETSTRUCT(tuple);

                initStringInfo(&rel);
                getRelationDescription(&rel, form_policy->polrelid);

                /* translator: second %s is, e.g., "table %s" */
                appendStringInfo(&buffer, _("policy %s on %s"),
                                 NameStr(form_policy->polname), rel.data);
                pfree(rel.data);
                systable_endscan(sscan);
                table_close(policy_rel, AccessShareLock);
                break;
            }

        case OCLASS_PUBLICATION:
            {
                appendStringInfo(&buffer, _("publication %s"),
                                 get_publication_name(object->objectId,
                                                      false));
                break;
            }

        case OCLASS_PUBLICATION_REL:
            {
                HeapTuple   tup;
                char       *pubname;
                Form_pg_publication_rel prform;
                StringInfoData rel;

                tup = SearchSysCache1(PUBLICATIONREL,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for publication table %u",
                         object->objectId);

                prform = (Form_pg_publication_rel) GETSTRUCT(tup);
                pubname = get_publication_name(prform->prpubid, false);

                initStringInfo(&rel);
                getRelationDescription(&rel, prform->prrelid);

                /* translator: first %s is, e.g., "table %s" */
                appendStringInfo(&buffer, _("publication of %s in publication %s"),
                                 rel.data, pubname);
                pfree(rel.data);
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_SUBSCRIPTION:
            {
                appendStringInfo(&buffer, _("subscription %s"),
                                 get_subscription_name(object->objectId,
                                                       false));
                break;
            }

        case OCLASS_TRANSFORM:
            {
                HeapTuple   trfTup;
                Form_pg_transform trfForm;

                trfTup = SearchSysCache1(TRFOID,
                                         ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(trfTup))
                    elog(ERROR, "could not find tuple for transform %u",
                         object->objectId);

                trfForm = (Form_pg_transform) GETSTRUCT(trfTup);

                appendStringInfo(&buffer, _("transform for %s language %s"),
                                 format_type_be(trfForm->trftype),
                                 get_language_name(trfForm->trflang, false));

                ReleaseSysCache(trfTup);
                break;
            }

            /*
             * There's intentionally no default: case here; we want the
             * compiler to warn if a new OCLASS hasn't been handled above.
             */
    }

    return buffer.data;
}

/*
 * getObjectDescriptionOids: as above, except the object is specified by Oids
 */
char *
getObjectDescriptionOids(Oid classid, Oid objid)
{
    ObjectAddress address;

    address.classId = classid;
    address.objectId = objid;
    address.objectSubId = 0;

    return getObjectDescription(&address);
}

/*
 * subroutine for getObjectDescription: describe a relation
 *
 * The result is appended to "buffer".
 */
static void
getRelationDescription(StringInfo buffer, Oid relid)
{
    HeapTuple   relTup;
    Form_pg_class relForm;
    char       *nspname;
    char       *relname;

    relTup = SearchSysCache1(RELOID,
                             ObjectIdGetDatum(relid));
    if (!HeapTupleIsValid(relTup))
        elog(ERROR, "cache lookup failed for relation %u", relid);
    relForm = (Form_pg_class) GETSTRUCT(relTup);

    /* Qualify the name if not visible in search path */
    if (RelationIsVisible(relid))
        nspname = NULL;
    else
        nspname = get_namespace_name(relForm->relnamespace);

    relname = quote_qualified_identifier(nspname, NameStr(relForm->relname));

    switch (relForm->relkind)
    {
        case RELKIND_RELATION:
        case RELKIND_PARTITIONED_TABLE:
            appendStringInfo(buffer, _("table %s"),
                             relname);
            break;
        case RELKIND_INDEX:
        case RELKIND_PARTITIONED_INDEX:
            appendStringInfo(buffer, _("index %s"),
                             relname);
            break;
        case RELKIND_SEQUENCE:
            appendStringInfo(buffer, _("sequence %s"),
                             relname);
            break;
        case RELKIND_TOASTVALUE:
            appendStringInfo(buffer, _("toast table %s"),
                             relname);
            break;
        case RELKIND_VIEW:
            appendStringInfo(buffer, _("view %s"),
                             relname);
            break;
        case RELKIND_MATVIEW:
            appendStringInfo(buffer, _("materialized view %s"),
                             relname);
            break;
        case RELKIND_COMPOSITE_TYPE:
            appendStringInfo(buffer, _("composite type %s"),
                             relname);
            break;
        case RELKIND_FOREIGN_TABLE:
            appendStringInfo(buffer, _("foreign table %s"),
                             relname);
            break;
        default:
            /* shouldn't get here */
            appendStringInfo(buffer, _("relation %s"),
                             relname);
            break;
    }

    ReleaseSysCache(relTup);
}

/*
 * subroutine for getObjectDescription: describe an operator family
 */
static void
getOpFamilyDescription(StringInfo buffer, Oid opfid)
{
    HeapTuple   opfTup;
    Form_pg_opfamily opfForm;
    HeapTuple   amTup;
    Form_pg_am  amForm;
    char       *nspname;

    opfTup = SearchSysCache1(OPFAMILYOID, ObjectIdGetDatum(opfid));
    if (!HeapTupleIsValid(opfTup))
        elog(ERROR, "cache lookup failed for opfamily %u", opfid);
    opfForm = (Form_pg_opfamily) GETSTRUCT(opfTup);

    amTup = SearchSysCache1(AMOID, ObjectIdGetDatum(opfForm->opfmethod));
    if (!HeapTupleIsValid(amTup))
        elog(ERROR, "cache lookup failed for access method %u",
             opfForm->opfmethod);
    amForm = (Form_pg_am) GETSTRUCT(amTup);

    /* Qualify the name if not visible in search path */
    if (OpfamilyIsVisible(opfid))
        nspname = NULL;
    else
        nspname = get_namespace_name(opfForm->opfnamespace);

    appendStringInfo(buffer, _("operator family %s for access method %s"),
                     quote_qualified_identifier(nspname,
                                                NameStr(opfForm->opfname)),
                     NameStr(amForm->amname));

    ReleaseSysCache(amTup);
    ReleaseSysCache(opfTup);
}

/*
 * SQL-level callable version of getObjectDescription
 */
Datum
pg_describe_object(PG_FUNCTION_ARGS)
{
    Oid         classid = PG_GETARG_OID(0);
    Oid         objid = PG_GETARG_OID(1);
    int32       objsubid = PG_GETARG_INT32(2);
    char       *description;
    ObjectAddress address;

    /* for "pinned" items in pg_depend, return null */
    if (!OidIsValid(classid) && !OidIsValid(objid))
        PG_RETURN_NULL();

    address.classId = classid;
    address.objectId = objid;
    address.objectSubId = objsubid;

    description = getObjectDescription(&address);
    PG_RETURN_TEXT_P(cstring_to_text(description));
}

/*
 * SQL-level callable function to obtain object type + identity
 */
Datum
pg_identify_object(PG_FUNCTION_ARGS)
{
    Oid         classid = PG_GETARG_OID(0);
    Oid         objid = PG_GETARG_OID(1);
    int32       objsubid = PG_GETARG_INT32(2);
    Oid         schema_oid = InvalidOid;
    const char *objname = NULL;
    ObjectAddress address;
    Datum       values[4];
    bool        nulls[4];
    TupleDesc   tupdesc;
    HeapTuple   htup;

    address.classId = classid;
    address.objectId = objid;
    address.objectSubId = objsubid;

    /*
     * Construct a tuple descriptor for the result row.  This must match this
     * function's pg_proc entry!
     */
    tupdesc = CreateTemplateTupleDesc(4);
    TupleDescInitEntry(tupdesc, (AttrNumber) 1, "type",
                       TEXTOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 2, "schema",
                       TEXTOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 3, "name",
                       TEXTOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 4, "identity",
                       TEXTOID, -1, 0);

    tupdesc = BlessTupleDesc(tupdesc);

    if (is_objectclass_supported(address.classId))
    {
        HeapTuple   objtup;
        Relation    catalog = table_open(address.classId, AccessShareLock);

        objtup = get_catalog_object_by_oid(catalog,
                                           get_object_attnum_oid(address.classId),
                                           address.objectId);
        if (objtup != NULL)
        {
            bool        isnull;
            AttrNumber  nspAttnum;
            AttrNumber  nameAttnum;

            nspAttnum = get_object_attnum_namespace(address.classId);
            if (nspAttnum != InvalidAttrNumber)
            {
                schema_oid = heap_getattr(objtup, nspAttnum,
                                          RelationGetDescr(catalog), &isnull);
                if (isnull)
                    elog(ERROR, "invalid null namespace in object %u/%u/%d",
                         address.classId, address.objectId, address.objectSubId);
            }

            /*
             * We only return the object name if it can be used (together with
             * the schema name, if any) as a unique identifier.
             */
            if (get_object_namensp_unique(address.classId))
            {
                nameAttnum = get_object_attnum_name(address.classId);
                if (nameAttnum != InvalidAttrNumber)
                {
                    Datum       nameDatum;

                    nameDatum = heap_getattr(objtup, nameAttnum,
                                             RelationGetDescr(catalog), &isnull);
                    if (isnull)
                        elog(ERROR, "invalid null name in object %u/%u/%d",
                             address.classId, address.objectId, address.objectSubId);
                    objname = quote_identifier(NameStr(*(DatumGetName(nameDatum))));
                }
            }
        }

        table_close(catalog, AccessShareLock);
    }

    /* object type */
    values[0] = CStringGetTextDatum(getObjectTypeDescription(&address));
    nulls[0] = false;

    /* schema name */
    if (OidIsValid(schema_oid))
    {
        const char *schema = quote_identifier(get_namespace_name(schema_oid));

        values[1] = CStringGetTextDatum(schema);
        nulls[1] = false;
    }
    else
        nulls[1] = true;

    /* object name */
    if (objname)
    {
        values[2] = CStringGetTextDatum(objname);
        nulls[2] = false;
    }
    else
        nulls[2] = true;

    /* object identity */
    values[3] = CStringGetTextDatum(getObjectIdentity(&address));
    nulls[3] = false;

    htup = heap_form_tuple(tupdesc, values, nulls);

    PG_RETURN_DATUM(HeapTupleGetDatum(htup));
}

/*
 * SQL-level callable function to obtain object type + identity
 */
Datum
pg_identify_object_as_address(PG_FUNCTION_ARGS)
{
    Oid         classid = PG_GETARG_OID(0);
    Oid         objid = PG_GETARG_OID(1);
    int32       objsubid = PG_GETARG_INT32(2);
    ObjectAddress address;
    char       *identity;
    List       *names;
    List       *args;
    Datum       values[3];
    bool        nulls[3];
    TupleDesc   tupdesc;
    HeapTuple   htup;

    address.classId = classid;
    address.objectId = objid;
    address.objectSubId = objsubid;

    /*
     * Construct a tuple descriptor for the result row.  This must match this
     * function's pg_proc entry!
     */
    tupdesc = CreateTemplateTupleDesc(3);
    TupleDescInitEntry(tupdesc, (AttrNumber) 1, "type",
                       TEXTOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 2, "object_names",
                       TEXTARRAYOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 3, "object_args",
                       TEXTARRAYOID, -1, 0);

    tupdesc = BlessTupleDesc(tupdesc);

    /* object type */
    values[0] = CStringGetTextDatum(getObjectTypeDescription(&address));
    nulls[0] = false;

    /* object identity */
    identity = getObjectIdentityParts(&address, &names, &args);
    pfree(identity);

    /* object_names */
    if (names != NIL)
        values[1] = PointerGetDatum(strlist_to_textarray(names));
    else
        values[1] = PointerGetDatum(construct_empty_array(TEXTOID));
    nulls[1] = false;

    /* object_args */
    if (args)
        values[2] = PointerGetDatum(strlist_to_textarray(args));
    else
        values[2] = PointerGetDatum(construct_empty_array(TEXTOID));
    nulls[2] = false;

    htup = heap_form_tuple(tupdesc, values, nulls);

    PG_RETURN_DATUM(HeapTupleGetDatum(htup));
}

/*
 * Return a palloc'ed string that describes the type of object that the
 * passed address is for.
 *
 * Keep ObjectTypeMap in sync with this.
 */
char *
getObjectTypeDescription(const ObjectAddress *object)
{
    StringInfoData buffer;

    initStringInfo(&buffer);

    switch (getObjectClass(object))
    {
        case OCLASS_CLASS:
            getRelationTypeDescription(&buffer, object->objectId,
                                       object->objectSubId);
            break;

        case OCLASS_PROC:
            getProcedureTypeDescription(&buffer, object->objectId);
            break;

        case OCLASS_TYPE:
            appendStringInfoString(&buffer, "type");
            break;

        case OCLASS_CAST:
            appendStringInfoString(&buffer, "cast");
            break;

        case OCLASS_COLLATION:
            appendStringInfoString(&buffer, "collation");
            break;

        case OCLASS_CONSTRAINT:
            getConstraintTypeDescription(&buffer, object->objectId);
            break;

        case OCLASS_CONVERSION:
            appendStringInfoString(&buffer, "conversion");
            break;

        case OCLASS_DEFAULT:
            appendStringInfoString(&buffer, "default value");
            break;

        case OCLASS_LANGUAGE:
            appendStringInfoString(&buffer, "language");
            break;

        case OCLASS_LARGEOBJECT:
            appendStringInfoString(&buffer, "large object");
            break;

        case OCLASS_OPERATOR:
            appendStringInfoString(&buffer, "operator");
            break;

        case OCLASS_OPCLASS:
            appendStringInfoString(&buffer, "operator class");
            break;

        case OCLASS_OPFAMILY:
            appendStringInfoString(&buffer, "operator family");
            break;

        case OCLASS_AM:
            appendStringInfoString(&buffer, "access method");
            break;

        case OCLASS_AMOP:
            appendStringInfoString(&buffer, "operator of access method");
            break;

        case OCLASS_AMPROC:
            appendStringInfoString(&buffer, "function of access method");
            break;

        case OCLASS_REWRITE:
            appendStringInfoString(&buffer, "rule");
            break;

        case OCLASS_TRIGGER:
            appendStringInfoString(&buffer, "trigger");
            break;

        case OCLASS_SCHEMA:
            appendStringInfoString(&buffer, "schema");
            break;

        case OCLASS_STATISTIC_EXT:
            appendStringInfoString(&buffer, "statistics object");
            break;

        case OCLASS_TSPARSER:
            appendStringInfoString(&buffer, "text search parser");
            break;

        case OCLASS_TSDICT:
            appendStringInfoString(&buffer, "text search dictionary");
            break;

        case OCLASS_TSTEMPLATE:
            appendStringInfoString(&buffer, "text search template");
            break;

        case OCLASS_TSCONFIG:
            appendStringInfoString(&buffer, "text search configuration");
            break;

        case OCLASS_ROLE:
            appendStringInfoString(&buffer, "role");
            break;

        case OCLASS_DATABASE:
            appendStringInfoString(&buffer, "database");
            break;

        case OCLASS_TBLSPACE:
            appendStringInfoString(&buffer, "tablespace");
            break;

        case OCLASS_FDW:
            appendStringInfoString(&buffer, "foreign-data wrapper");
            break;

        case OCLASS_FOREIGN_SERVER:
            appendStringInfoString(&buffer, "server");
            break;

        case OCLASS_USER_MAPPING:
            appendStringInfoString(&buffer, "user mapping");
            break;

        case OCLASS_DEFACL:
            appendStringInfoString(&buffer, "default acl");
            break;

        case OCLASS_EXTENSION:
            appendStringInfoString(&buffer, "extension");
            break;

        case OCLASS_EVENT_TRIGGER:
            appendStringInfoString(&buffer, "event trigger");
            break;

        case OCLASS_POLICY:
            appendStringInfoString(&buffer, "policy");
            break;

        case OCLASS_PUBLICATION:
            appendStringInfoString(&buffer, "publication");
            break;

        case OCLASS_PUBLICATION_REL:
            appendStringInfoString(&buffer, "publication relation");
            break;

        case OCLASS_SUBSCRIPTION:
            appendStringInfoString(&buffer, "subscription");
            break;

        case OCLASS_TRANSFORM:
            appendStringInfoString(&buffer, "transform");
            break;

            /*
             * There's intentionally no default: case here; we want the
             * compiler to warn if a new OCLASS hasn't been handled above.
             */
    }

    return buffer.data;
}

/*
 * subroutine for getObjectTypeDescription: describe a relation type
 */
static void
getRelationTypeDescription(StringInfo buffer, Oid relid, int32 objectSubId)
{
    HeapTuple   relTup;
    Form_pg_class relForm;

    relTup = SearchSysCache1(RELOID,
                             ObjectIdGetDatum(relid));
    if (!HeapTupleIsValid(relTup))
        elog(ERROR, "cache lookup failed for relation %u", relid);
    relForm = (Form_pg_class) GETSTRUCT(relTup);

    switch (relForm->relkind)
    {
        case RELKIND_RELATION:
        case RELKIND_PARTITIONED_TABLE:
            appendStringInfoString(buffer, "table");
            break;
        case RELKIND_INDEX:
        case RELKIND_PARTITIONED_INDEX:
            appendStringInfoString(buffer, "index");
            break;
        case RELKIND_SEQUENCE:
            appendStringInfoString(buffer, "sequence");
            break;
        case RELKIND_TOASTVALUE:
            appendStringInfoString(buffer, "toast table");
            break;
        case RELKIND_VIEW:
            appendStringInfoString(buffer, "view");
            break;
        case RELKIND_MATVIEW:
            appendStringInfoString(buffer, "materialized view");
            break;
        case RELKIND_COMPOSITE_TYPE:
            appendStringInfoString(buffer, "composite type");
            break;
        case RELKIND_FOREIGN_TABLE:
            appendStringInfoString(buffer, "foreign table");
            break;
        default:
            /* shouldn't get here */
            appendStringInfoString(buffer, "relation");
            break;
    }

    if (objectSubId != 0)
        appendStringInfoString(buffer, " column");

    ReleaseSysCache(relTup);
}

/*
 * subroutine for getObjectTypeDescription: describe a constraint type
 */
static void
getConstraintTypeDescription(StringInfo buffer, Oid constroid)
{
    Relation    constrRel;
    HeapTuple   constrTup;
    Form_pg_constraint constrForm;

    constrRel = table_open(ConstraintRelationId, AccessShareLock);
    constrTup = get_catalog_object_by_oid(constrRel, Anum_pg_constraint_oid,
                                          constroid);
    if (!HeapTupleIsValid(constrTup))
        elog(ERROR, "cache lookup failed for constraint %u", constroid);

    constrForm = (Form_pg_constraint) GETSTRUCT(constrTup);

    if (OidIsValid(constrForm->conrelid))
        appendStringInfoString(buffer, "table constraint");
    else if (OidIsValid(constrForm->contypid))
        appendStringInfoString(buffer, "domain constraint");
    else
        elog(ERROR, "invalid constraint %u", constrForm->oid);

    table_close(constrRel, AccessShareLock);
}

/*
 * subroutine for getObjectTypeDescription: describe a procedure type
 */
static void
getProcedureTypeDescription(StringInfo buffer, Oid procid)
{
    HeapTuple   procTup;
    Form_pg_proc procForm;

    procTup = SearchSysCache1(PROCOID,
                              ObjectIdGetDatum(procid));
    if (!HeapTupleIsValid(procTup))
        elog(ERROR, "cache lookup failed for procedure %u", procid);
    procForm = (Form_pg_proc) GETSTRUCT(procTup);

    if (procForm->prokind == PROKIND_AGGREGATE)
        appendStringInfoString(buffer, "aggregate");
    else if (procForm->prokind == PROKIND_PROCEDURE)
        appendStringInfoString(buffer, "procedure");
    else                        /* function or window function */
        appendStringInfoString(buffer, "function");

    ReleaseSysCache(procTup);
}

/*
 * Obtain a given object's identity, as a palloc'ed string.
 *
 * This is for machine consumption, so it's not translated.  All elements are
 * schema-qualified when appropriate.
 */
char *
getObjectIdentity(const ObjectAddress *object)
{
    return getObjectIdentityParts(object, NULL, NULL);
}

/*
 * As above, but more detailed.
 *
 * There are two sets of return values: the identity itself as a palloc'd
 * string is returned.  objname and objargs, if not NULL, are output parameters
 * that receive lists of C-strings that are useful to give back to
 * get_object_address() to reconstruct the ObjectAddress.
 */
char *
getObjectIdentityParts(const ObjectAddress *object,
                       List **objname, List **objargs)
{
    StringInfoData buffer;

    initStringInfo(&buffer);

    /*
     * Make sure that both objname and objargs were passed, or none was; and
     * initialize them to empty lists.  For objname this is useless because it
     * will be initialized in all cases inside the switch; but we do it anyway
     * so that we can test below that no branch leaves it unset.
     */
    Assert(PointerIsValid(objname) == PointerIsValid(objargs));
    if (objname)
    {
        *objname = NIL;
        *objargs = NIL;
    }

    switch (getObjectClass(object))
    {
        case OCLASS_CLASS:
            getRelationIdentity(&buffer, object->objectId, objname);
            if (object->objectSubId != 0)
            {
                char       *attr;

                attr = get_attname(object->objectId, object->objectSubId,
                                   false);
                appendStringInfo(&buffer, ".%s", quote_identifier(attr));
                if (objname)
                    *objname = lappend(*objname, attr);
            }
            break;

        case OCLASS_PROC:
            appendStringInfoString(&buffer,
                                   format_procedure_qualified(object->objectId));
            if (objname)
                format_procedure_parts(object->objectId, objname, objargs);
            break;

        case OCLASS_TYPE:
            {
                char       *typeout;

                typeout = format_type_be_qualified(object->objectId);
                appendStringInfoString(&buffer, typeout);
                if (objname)
                    *objname = list_make1(typeout);
            }
            break;

        case OCLASS_CAST:
            {
                Relation    castRel;
                HeapTuple   tup;
                Form_pg_cast castForm;

                castRel = table_open(CastRelationId, AccessShareLock);

                tup = get_catalog_object_by_oid(castRel, Anum_pg_cast_oid,
                                                object->objectId);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for cast %u",
                         object->objectId);

                castForm = (Form_pg_cast) GETSTRUCT(tup);

                appendStringInfo(&buffer, "(%s AS %s)",
                                 format_type_be_qualified(castForm->castsource),
                                 format_type_be_qualified(castForm->casttarget));

                if (objname)
                {
                    *objname = list_make1(format_type_be_qualified(castForm->castsource));
                    *objargs = list_make1(format_type_be_qualified(castForm->casttarget));
                }

                table_close(castRel, AccessShareLock);
                break;
            }

        case OCLASS_COLLATION:
            {
                HeapTuple   collTup;
                Form_pg_collation coll;
                char       *schema;

                collTup = SearchSysCache1(COLLOID,
                                          ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(collTup))
                    elog(ERROR, "cache lookup failed for collation %u",
                         object->objectId);
                coll = (Form_pg_collation) GETSTRUCT(collTup);
                schema = get_namespace_name_or_temp(coll->collnamespace);
                appendStringInfoString(&buffer,
                                       quote_qualified_identifier(schema,
                                                                  NameStr(coll->collname)));
                if (objname)
                    *objname = list_make2(schema,
                                          pstrdup(NameStr(coll->collname)));
                ReleaseSysCache(collTup);
                break;
            }

        case OCLASS_CONSTRAINT:
            {
                HeapTuple   conTup;
                Form_pg_constraint con;

                conTup = SearchSysCache1(CONSTROID,
                                         ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(conTup))
                    elog(ERROR, "cache lookup failed for constraint %u",
                         object->objectId);
                con = (Form_pg_constraint) GETSTRUCT(conTup);

                if (OidIsValid(con->conrelid))
                {
                    appendStringInfo(&buffer, "%s on ",
                                     quote_identifier(NameStr(con->conname)));
                    getRelationIdentity(&buffer, con->conrelid, objname);
                    if (objname)
                        *objname = lappend(*objname, pstrdup(NameStr(con->conname)));
                }
                else
                {
                    ObjectAddress domain;

                    Assert(OidIsValid(con->contypid));
                    domain.classId = TypeRelationId;
                    domain.objectId = con->contypid;
                    domain.objectSubId = 0;

                    appendStringInfo(&buffer, "%s on %s",
                                     quote_identifier(NameStr(con->conname)),
                                     getObjectIdentityParts(&domain, objname, objargs));

                    if (objname)
                        *objargs = lappend(*objargs, pstrdup(NameStr(con->conname)));
                }

                ReleaseSysCache(conTup);
                break;
            }

        case OCLASS_CONVERSION:
            {
                HeapTuple   conTup;
                Form_pg_conversion conForm;
                char       *schema;

                conTup = SearchSysCache1(CONVOID,
                                         ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(conTup))
                    elog(ERROR, "cache lookup failed for conversion %u",
                         object->objectId);
                conForm = (Form_pg_conversion) GETSTRUCT(conTup);
                schema = get_namespace_name_or_temp(conForm->connamespace);
                appendStringInfoString(&buffer,
                                       quote_qualified_identifier(schema,
                                                                  NameStr(conForm->conname)));
                if (objname)
                    *objname = list_make2(schema,
                                          pstrdup(NameStr(conForm->conname)));
                ReleaseSysCache(conTup);
                break;
            }

        case OCLASS_DEFAULT:
            {
                Relation    attrdefDesc;
                ScanKeyData skey[1];
                SysScanDesc adscan;

                HeapTuple   tup;
                Form_pg_attrdef attrdef;
                ObjectAddress colobject;

                attrdefDesc = table_open(AttrDefaultRelationId, AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_attrdef_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                adscan = systable_beginscan(attrdefDesc, AttrDefaultOidIndexId,
                                            true, NULL, 1, skey);

                tup = systable_getnext(adscan);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for attrdef %u",
                         object->objectId);

                attrdef = (Form_pg_attrdef) GETSTRUCT(tup);

                colobject.classId = RelationRelationId;
                colobject.objectId = attrdef->adrelid;
                colobject.objectSubId = attrdef->adnum;

                appendStringInfo(&buffer, "for %s",
                                 getObjectIdentityParts(&colobject,
                                                        objname, objargs));

                systable_endscan(adscan);
                table_close(attrdefDesc, AccessShareLock);
                break;
            }

        case OCLASS_LANGUAGE:
            {
                HeapTuple   langTup;
                Form_pg_language langForm;

                langTup = SearchSysCache1(LANGOID,
                                          ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(langTup))
                    elog(ERROR, "cache lookup failed for language %u",
                         object->objectId);
                langForm = (Form_pg_language) GETSTRUCT(langTup);
                appendStringInfoString(&buffer,
                                       quote_identifier(NameStr(langForm->lanname)));
                if (objname)
                    *objname = list_make1(pstrdup(NameStr(langForm->lanname)));
                ReleaseSysCache(langTup);
                break;
            }
        case OCLASS_LARGEOBJECT:
            appendStringInfo(&buffer, "%u",
                             object->objectId);
            if (objname)
                *objname = list_make1(psprintf("%u", object->objectId));
            break;

        case OCLASS_OPERATOR:
            appendStringInfoString(&buffer,
                                   format_operator_qualified(object->objectId));
            if (objname)
                format_operator_parts(object->objectId, objname, objargs);
            break;

        case OCLASS_OPCLASS:
            {
                HeapTuple   opcTup;
                Form_pg_opclass opcForm;
                HeapTuple   amTup;
                Form_pg_am  amForm;
                char       *schema;

                opcTup = SearchSysCache1(CLAOID,
                                         ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(opcTup))
                    elog(ERROR, "cache lookup failed for opclass %u",
                         object->objectId);
                opcForm = (Form_pg_opclass) GETSTRUCT(opcTup);
                schema = get_namespace_name_or_temp(opcForm->opcnamespace);

                amTup = SearchSysCache1(AMOID,
                                        ObjectIdGetDatum(opcForm->opcmethod));
                if (!HeapTupleIsValid(amTup))
                    elog(ERROR, "cache lookup failed for access method %u",
                         opcForm->opcmethod);
                amForm = (Form_pg_am) GETSTRUCT(amTup);

                appendStringInfo(&buffer, "%s USING %s",
                                 quote_qualified_identifier(schema,
                                                            NameStr(opcForm->opcname)),
                                 quote_identifier(NameStr(amForm->amname)));
                if (objname)
                    *objname = list_make3(pstrdup(NameStr(amForm->amname)),
                                          schema,
                                          pstrdup(NameStr(opcForm->opcname)));

                ReleaseSysCache(amTup);
                ReleaseSysCache(opcTup);
                break;
            }

        case OCLASS_OPFAMILY:
            getOpFamilyIdentity(&buffer, object->objectId, objname);
            break;

        case OCLASS_AM:
            {
                char       *amname;

                amname = get_am_name(object->objectId);
                if (!amname)
                    elog(ERROR, "cache lookup failed for access method %u",
                         object->objectId);
                appendStringInfoString(&buffer, quote_identifier(amname));
                if (objname)
                    *objname = list_make1(amname);
            }
            break;

        case OCLASS_AMOP:
            {
                Relation    amopDesc;
                HeapTuple   tup;
                ScanKeyData skey[1];
                SysScanDesc amscan;
                Form_pg_amop amopForm;
                StringInfoData opfam;
                char       *ltype;
                char       *rtype;

                amopDesc = table_open(AccessMethodOperatorRelationId,
                                      AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_amop_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                amscan = systable_beginscan(amopDesc, AccessMethodOperatorOidIndexId, true,
                                            NULL, 1, skey);

                tup = systable_getnext(amscan);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for amop entry %u",
                         object->objectId);

                amopForm = (Form_pg_amop) GETSTRUCT(tup);

                initStringInfo(&opfam);
                getOpFamilyIdentity(&opfam, amopForm->amopfamily, objname);

                ltype = format_type_be_qualified(amopForm->amoplefttype);
                rtype = format_type_be_qualified(amopForm->amoprighttype);

                if (objname)
                {
                    *objname = lappend(*objname,
                                       psprintf("%d", amopForm->amopstrategy));
                    *objargs = list_make2(ltype, rtype);
                }

                appendStringInfo(&buffer, "operator %d (%s, %s) of %s",
                                 amopForm->amopstrategy,
                                 ltype, rtype, opfam.data);

                pfree(opfam.data);

                systable_endscan(amscan);
                table_close(amopDesc, AccessShareLock);
                break;
            }

        case OCLASS_AMPROC:
            {
                Relation    amprocDesc;
                ScanKeyData skey[1];
                SysScanDesc amscan;
                HeapTuple   tup;
                Form_pg_amproc amprocForm;
                StringInfoData opfam;
                char       *ltype;
                char       *rtype;

                amprocDesc = table_open(AccessMethodProcedureRelationId,
                                        AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_amproc_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                amscan = systable_beginscan(amprocDesc, AccessMethodProcedureOidIndexId, true,
                                            NULL, 1, skey);

                tup = systable_getnext(amscan);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for amproc entry %u",
                         object->objectId);

                amprocForm = (Form_pg_amproc) GETSTRUCT(tup);

                initStringInfo(&opfam);
                getOpFamilyIdentity(&opfam, amprocForm->amprocfamily, objname);

                ltype = format_type_be_qualified(amprocForm->amproclefttype);
                rtype = format_type_be_qualified(amprocForm->amprocrighttype);

                if (objname)
                {
                    *objname = lappend(*objname,
                                       psprintf("%d", amprocForm->amprocnum));
                    *objargs = list_make2(ltype, rtype);
                }

                appendStringInfo(&buffer, "function %d (%s, %s) of %s",
                                 amprocForm->amprocnum,
                                 ltype, rtype, opfam.data);

                pfree(opfam.data);

                systable_endscan(amscan);
                table_close(amprocDesc, AccessShareLock);
                break;
            }

        case OCLASS_REWRITE:
            {
                Relation    ruleDesc;
                HeapTuple   tup;
                Form_pg_rewrite rule;

                ruleDesc = table_open(RewriteRelationId, AccessShareLock);

                tup = get_catalog_object_by_oid(ruleDesc, Anum_pg_rewrite_oid,
                                                object->objectId);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for rule %u",
                         object->objectId);

                rule = (Form_pg_rewrite) GETSTRUCT(tup);

                appendStringInfo(&buffer, "%s on ",
                                 quote_identifier(NameStr(rule->rulename)));
                getRelationIdentity(&buffer, rule->ev_class, objname);
                if (objname)
                    *objname = lappend(*objname, pstrdup(NameStr(rule->rulename)));

                table_close(ruleDesc, AccessShareLock);
                break;
            }

        case OCLASS_TRIGGER:
            {
                Relation    trigDesc;
                HeapTuple   tup;
                Form_pg_trigger trig;

                trigDesc = table_open(TriggerRelationId, AccessShareLock);

                tup = get_catalog_object_by_oid(trigDesc, Anum_pg_trigger_oid,
                                                object->objectId);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for trigger %u",
                         object->objectId);

                trig = (Form_pg_trigger) GETSTRUCT(tup);

                appendStringInfo(&buffer, "%s on ",
                                 quote_identifier(NameStr(trig->tgname)));
                getRelationIdentity(&buffer, trig->tgrelid, objname);
                if (objname)
                    *objname = lappend(*objname, pstrdup(NameStr(trig->tgname)));

                table_close(trigDesc, AccessShareLock);
                break;
            }

        case OCLASS_SCHEMA:
            {
                char       *nspname;

                nspname = get_namespace_name_or_temp(object->objectId);
                if (!nspname)
                    elog(ERROR, "cache lookup failed for namespace %u",
                         object->objectId);
                appendStringInfoString(&buffer,
                                       quote_identifier(nspname));
                if (objname)
                    *objname = list_make1(nspname);
                break;
            }

        case OCLASS_STATISTIC_EXT:
            {
                HeapTuple   tup;
                Form_pg_statistic_ext formStatistic;
                char       *schema;

                tup = SearchSysCache1(STATEXTOID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for statistics object %u",
                         object->objectId);
                formStatistic = (Form_pg_statistic_ext) GETSTRUCT(tup);
                schema = get_namespace_name_or_temp(formStatistic->stxnamespace);
                appendStringInfoString(&buffer,
                                       quote_qualified_identifier(schema,
                                                                  NameStr(formStatistic->stxname)));
                if (objname)
                    *objname = list_make2(schema,
                                          pstrdup(NameStr(formStatistic->stxname)));
                ReleaseSysCache(tup);
            }
            break;

        case OCLASS_TSPARSER:
            {
                HeapTuple   tup;
                Form_pg_ts_parser formParser;
                char       *schema;

                tup = SearchSysCache1(TSPARSEROID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for text search parser %u",
                         object->objectId);
                formParser = (Form_pg_ts_parser) GETSTRUCT(tup);
                schema = get_namespace_name_or_temp(formParser->prsnamespace);
                appendStringInfoString(&buffer,
                                       quote_qualified_identifier(schema,
                                                                  NameStr(formParser->prsname)));
                if (objname)
                    *objname = list_make2(schema,
                                          pstrdup(NameStr(formParser->prsname)));
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_TSDICT:
            {
                HeapTuple   tup;
                Form_pg_ts_dict formDict;
                char       *schema;

                tup = SearchSysCache1(TSDICTOID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for text search dictionary %u",
                         object->objectId);
                formDict = (Form_pg_ts_dict) GETSTRUCT(tup);
                schema = get_namespace_name_or_temp(formDict->dictnamespace);
                appendStringInfoString(&buffer,
                                       quote_qualified_identifier(schema,
                                                                  NameStr(formDict->dictname)));
                if (objname)
                    *objname = list_make2(schema,
                                          pstrdup(NameStr(formDict->dictname)));
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_TSTEMPLATE:
            {
                HeapTuple   tup;
                Form_pg_ts_template formTmpl;
                char       *schema;

                tup = SearchSysCache1(TSTEMPLATEOID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for text search template %u",
                         object->objectId);
                formTmpl = (Form_pg_ts_template) GETSTRUCT(tup);
                schema = get_namespace_name_or_temp(formTmpl->tmplnamespace);
                appendStringInfoString(&buffer,
                                       quote_qualified_identifier(schema,
                                                                  NameStr(formTmpl->tmplname)));
                if (objname)
                    *objname = list_make2(schema,
                                          pstrdup(NameStr(formTmpl->tmplname)));
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_TSCONFIG:
            {
                HeapTuple   tup;
                Form_pg_ts_config formCfg;
                char       *schema;

                tup = SearchSysCache1(TSCONFIGOID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for text search configuration %u",
                         object->objectId);
                formCfg = (Form_pg_ts_config) GETSTRUCT(tup);
                schema = get_namespace_name_or_temp(formCfg->cfgnamespace);
                appendStringInfoString(&buffer,
                                       quote_qualified_identifier(schema,
                                                                  NameStr(formCfg->cfgname)));
                if (objname)
                    *objname = list_make2(schema,
                                          pstrdup(NameStr(formCfg->cfgname)));
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_ROLE:
            {
                char       *username;

                username = GetUserNameFromId(object->objectId, false);
                if (objname)
                    *objname = list_make1(username);
                appendStringInfoString(&buffer,
                                       quote_identifier(username));
                break;
            }

        case OCLASS_DATABASE:
            {
                char       *datname;

                datname = get_database_name(object->objectId);
                if (!datname)
                    elog(ERROR, "cache lookup failed for database %u",
                         object->objectId);
                if (objname)
                    *objname = list_make1(datname);
                appendStringInfoString(&buffer,
                                       quote_identifier(datname));
                break;
            }

        case OCLASS_TBLSPACE:
            {
                char       *tblspace;

                tblspace = get_tablespace_name(object->objectId);
                if (!tblspace)
                    elog(ERROR, "cache lookup failed for tablespace %u",
                         object->objectId);
                if (objname)
                    *objname = list_make1(tblspace);
                appendStringInfoString(&buffer,
                                       quote_identifier(tblspace));
                break;
            }

        case OCLASS_FDW:
            {
                ForeignDataWrapper *fdw;

                fdw = GetForeignDataWrapper(object->objectId);
                appendStringInfoString(&buffer, quote_identifier(fdw->fdwname));
                if (objname)
                    *objname = list_make1(pstrdup(fdw->fdwname));
                break;
            }

        case OCLASS_FOREIGN_SERVER:
            {
                ForeignServer *srv;

                srv = GetForeignServer(object->objectId);
                appendStringInfoString(&buffer,
                                       quote_identifier(srv->servername));
                if (objname)
                    *objname = list_make1(pstrdup(srv->servername));
                break;
            }

        case OCLASS_USER_MAPPING:
            {
                HeapTuple   tup;
                Oid         useid;
                Form_pg_user_mapping umform;
                ForeignServer *srv;
                const char *usename;

                tup = SearchSysCache1(USERMAPPINGOID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for user mapping %u",
                         object->objectId);
                umform = (Form_pg_user_mapping) GETSTRUCT(tup);
                useid = umform->umuser;
                srv = GetForeignServer(umform->umserver);

                ReleaseSysCache(tup);

                if (OidIsValid(useid))
                    usename = GetUserNameFromId(useid, false);
                else
                    usename = "public";

                if (objname)
                {
                    *objname = list_make1(pstrdup(usename));
                    *objargs = list_make1(pstrdup(srv->servername));
                }

                appendStringInfo(&buffer, "%s on server %s",
                                 quote_identifier(usename),
                                 srv->servername);
                break;
            }

        case OCLASS_DEFACL:
            {
                Relation    defaclrel;
                ScanKeyData skey[1];
                SysScanDesc rcscan;
                HeapTuple   tup;
                Form_pg_default_acl defacl;
                char       *schema;
                char       *username;

                defaclrel = table_open(DefaultAclRelationId, AccessShareLock);

                ScanKeyInit(&skey[0],
                            Anum_pg_default_acl_oid,
                            BTEqualStrategyNumber, F_OIDEQ,
                            ObjectIdGetDatum(object->objectId));

                rcscan = systable_beginscan(defaclrel, DefaultAclOidIndexId,
                                            true, NULL, 1, skey);

                tup = systable_getnext(rcscan);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for default ACL %u",
                         object->objectId);

                defacl = (Form_pg_default_acl) GETSTRUCT(tup);

                username = GetUserNameFromId(defacl->defaclrole, false);
                appendStringInfo(&buffer,
                                 "for role %s",
                                 quote_identifier(username));

                if (OidIsValid(defacl->defaclnamespace))
                {
                    schema = get_namespace_name_or_temp(defacl->defaclnamespace);
                    appendStringInfo(&buffer,
                                     " in schema %s",
                                     quote_identifier(schema));
                }
                else
                    schema = NULL;

                switch (defacl->defaclobjtype)
                {
                    case DEFACLOBJ_RELATION:
                        appendStringInfoString(&buffer,
                                               " on tables");
                        break;
                    case DEFACLOBJ_SEQUENCE:
                        appendStringInfoString(&buffer,
                                               " on sequences");
                        break;
                    case DEFACLOBJ_FUNCTION:
                        appendStringInfoString(&buffer,
                                               " on functions");
                        break;
                    case DEFACLOBJ_TYPE:
                        appendStringInfoString(&buffer,
                                               " on types");
                        break;
                    case DEFACLOBJ_NAMESPACE:
                        appendStringInfoString(&buffer,
                                               " on schemas");
                        break;
                }

                if (objname)
                {
                    *objname = list_make1(username);
                    if (schema)
                        *objname = lappend(*objname, schema);
                    *objargs = list_make1(psprintf("%c", defacl->defaclobjtype));
                }

                systable_endscan(rcscan);
                table_close(defaclrel, AccessShareLock);
                break;
            }

        case OCLASS_EXTENSION:
            {
                char       *extname;

                extname = get_extension_name(object->objectId);
                if (!extname)
                    elog(ERROR, "cache lookup failed for extension %u",
                         object->objectId);
                appendStringInfoString(&buffer, quote_identifier(extname));
                if (objname)
                    *objname = list_make1(extname);
                break;
            }

        case OCLASS_EVENT_TRIGGER:
            {
                HeapTuple   tup;
                Form_pg_event_trigger trigForm;

                /* no objname support here */
                if (objname)
                    *objname = NIL;

                tup = SearchSysCache1(EVENTTRIGGEROID,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for event trigger %u",
                         object->objectId);
                trigForm = (Form_pg_event_trigger) GETSTRUCT(tup);
                appendStringInfoString(&buffer,
                                       quote_identifier(NameStr(trigForm->evtname)));
                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_POLICY:
            {
                Relation    polDesc;
                HeapTuple   tup;
                Form_pg_policy policy;

                polDesc = table_open(PolicyRelationId, AccessShareLock);

                tup = get_catalog_object_by_oid(polDesc, Anum_pg_policy_oid,
                                                object->objectId);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for policy %u",
                         object->objectId);

                policy = (Form_pg_policy) GETSTRUCT(tup);

                appendStringInfo(&buffer, "%s on ",
                                 quote_identifier(NameStr(policy->polname)));
                getRelationIdentity(&buffer, policy->polrelid, objname);
                if (objname)
                    *objname = lappend(*objname, pstrdup(NameStr(policy->polname)));

                table_close(polDesc, AccessShareLock);
                break;
            }

        case OCLASS_PUBLICATION:
            {
                char       *pubname;

                pubname = get_publication_name(object->objectId, false);
                appendStringInfoString(&buffer,
                                       quote_identifier(pubname));
                if (objname)
                    *objname = list_make1(pubname);
                break;
            }

        case OCLASS_PUBLICATION_REL:
            {
                HeapTuple   tup;
                char       *pubname;
                Form_pg_publication_rel prform;

                tup = SearchSysCache1(PUBLICATIONREL,
                                      ObjectIdGetDatum(object->objectId));
                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "cache lookup failed for publication table %u",
                         object->objectId);

                prform = (Form_pg_publication_rel) GETSTRUCT(tup);
                pubname = get_publication_name(prform->prpubid, false);

                getRelationIdentity(&buffer, prform->prrelid, objname);
                appendStringInfo(&buffer, " in publication %s", pubname);

                if (objargs)
                    *objargs = list_make1(pubname);

                ReleaseSysCache(tup);
                break;
            }

        case OCLASS_SUBSCRIPTION:
            {
                char       *subname;

                subname = get_subscription_name(object->objectId, false);
                appendStringInfoString(&buffer,
                                       quote_identifier(subname));
                if (objname)
                    *objname = list_make1(subname);
                break;
            }

        case OCLASS_TRANSFORM:
            {
                Relation    transformDesc;
                HeapTuple   tup;
                Form_pg_transform transform;
                char       *transformLang;
                char       *transformType;

                transformDesc = table_open(TransformRelationId, AccessShareLock);

                tup = get_catalog_object_by_oid(transformDesc,
                                                Anum_pg_transform_oid,
                                                object->objectId);

                if (!HeapTupleIsValid(tup))
                    elog(ERROR, "could not find tuple for transform %u",
                         object->objectId);

                transform = (Form_pg_transform) GETSTRUCT(tup);

                transformType = format_type_be_qualified(transform->trftype);
                transformLang = get_language_name(transform->trflang, false);

                appendStringInfo(&buffer, "for %s on language %s",
                                 transformType,
                                 transformLang);
                if (objname)
                {
                    *objname = list_make1(transformType);
                    *objargs = list_make1(pstrdup(transformLang));
                }

                table_close(transformDesc, AccessShareLock);
            }
            break;

            /*
             * There's intentionally no default: case here; we want the
             * compiler to warn if a new OCLASS hasn't been handled above.
             */
    }

    /*
     * If a get_object_address representation was requested, make sure we are
     * providing one.  We don't check objargs, because many of the cases above
     * leave it as NIL.
     */
    if (objname && *objname == NIL)
        elog(ERROR, "requested object address for unsupported object class %d: text result \"%s\"",
             (int) getObjectClass(object), buffer.data);

    return buffer.data;
}

static void
getOpFamilyIdentity(StringInfo buffer, Oid opfid, List **object)
{
    HeapTuple   opfTup;
    Form_pg_opfamily opfForm;
    HeapTuple   amTup;
    Form_pg_am  amForm;
    char       *schema;

    opfTup = SearchSysCache1(OPFAMILYOID, ObjectIdGetDatum(opfid));
    if (!HeapTupleIsValid(opfTup))
        elog(ERROR, "cache lookup failed for opfamily %u", opfid);
    opfForm = (Form_pg_opfamily) GETSTRUCT(opfTup);

    amTup = SearchSysCache1(AMOID, ObjectIdGetDatum(opfForm->opfmethod));
    if (!HeapTupleIsValid(amTup))
        elog(ERROR, "cache lookup failed for access method %u",
             opfForm->opfmethod);
    amForm = (Form_pg_am) GETSTRUCT(amTup);

    schema = get_namespace_name_or_temp(opfForm->opfnamespace);
    appendStringInfo(buffer, "%s USING %s",
                     quote_qualified_identifier(schema,
                                                NameStr(opfForm->opfname)),
                     NameStr(amForm->amname));

    if (object)
        *object = list_make3(pstrdup(NameStr(amForm->amname)),
                             pstrdup(schema),
                             pstrdup(NameStr(opfForm->opfname)));

    ReleaseSysCache(amTup);
    ReleaseSysCache(opfTup);
}

/*
 * Append the relation identity (quoted qualified name) to the given
 * StringInfo.
 */
static void
getRelationIdentity(StringInfo buffer, Oid relid, List **object)
{
    HeapTuple   relTup;
    Form_pg_class relForm;
    char       *schema;

    relTup = SearchSysCache1(RELOID,
                             ObjectIdGetDatum(relid));
    if (!HeapTupleIsValid(relTup))
        elog(ERROR, "cache lookup failed for relation %u", relid);
    relForm = (Form_pg_class) GETSTRUCT(relTup);

    schema = get_namespace_name_or_temp(relForm->relnamespace);
    appendStringInfoString(buffer,
                           quote_qualified_identifier(schema,
                                                      NameStr(relForm->relname)));
    if (object)
        *object = list_make2(schema, pstrdup(NameStr(relForm->relname)));

    ReleaseSysCache(relTup);
}

/*
 * Auxiliary function to build a TEXT array out of a list of C-strings.
 */
ArrayType *
strlist_to_textarray(List *list)
{
    ArrayType  *arr;
    Datum      *datums;
    bool       *nulls;
    int         j = 0;
    ListCell   *cell;
    MemoryContext memcxt;
    MemoryContext oldcxt;
    int         lb[1];

    /* Work in a temp context; easier than individually pfree'ing the Datums */
    memcxt = AllocSetContextCreate(CurrentMemoryContext,
                                   "strlist to array",
                                   ALLOCSET_DEFAULT_SIZES);
    oldcxt = MemoryContextSwitchTo(memcxt);

    datums = (Datum *) palloc(sizeof(Datum) * list_length(list));
    nulls = palloc(sizeof(bool) * list_length(list));

    foreach(cell, list)
    {
        char       *name = lfirst(cell);

        if (name)
        {
            nulls[j] = false;
            datums[j++] = CStringGetTextDatum(name);
        }
        else
            nulls[j] = true;
    }

    MemoryContextSwitchTo(oldcxt);

    lb[0] = 1;
    arr = construct_md_array(datums, nulls, 1, &j,
                             lb, TEXTOID, -1, false, 'i');

    MemoryContextDelete(memcxt);

    return arr;
}

/*
 * get_relkind_objtype
 *
 * Return the object type for the relkind given by the caller.
 *
 * If an unexpected relkind is passed, we say OBJECT_TABLE rather than
 * failing.  That's because this is mostly used for generating error messages
 * for failed ACL checks on relations, and we'd rather produce a generic
 * message saying "table" than fail entirely.
 */
ObjectType
get_relkind_objtype(char relkind)
{
    switch (relkind)
    {
        case RELKIND_RELATION:
        case RELKIND_PARTITIONED_TABLE:
            return OBJECT_TABLE;
        case RELKIND_INDEX:
        case RELKIND_PARTITIONED_INDEX:
            return OBJECT_INDEX;
        case RELKIND_SEQUENCE:
            return OBJECT_SEQUENCE;
        case RELKIND_VIEW:
            return OBJECT_VIEW;
        case RELKIND_MATVIEW:
            return OBJECT_MATVIEW;
        case RELKIND_FOREIGN_TABLE:
            return OBJECT_FOREIGN_TABLE;
        case RELKIND_TOASTVALUE:
            return OBJECT_TABLE;
        default:
            /* Per above, don't raise an error */
            return OBJECT_TABLE;
    }
}