pg_class.h

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/*-------------------------------------------------------------------------
 *
 * pg_class.h
 *    definition of the "relation" system catalog (pg_class)
 *
 *
 * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/include/catalog/pg_class.h
 *
 * NOTES
 *    The Catalog.pm module reads this file and derives schema
 *    information.
 *
 *-------------------------------------------------------------------------
 */
#ifndef PG_CLASS_H
#define PG_CLASS_H

#include "catalog/genbki.h"
#include "catalog/pg_class_d.h"

/* ----------------
 *      pg_class definition.  cpp turns this into
 *      typedef struct FormData_pg_class
 *
 * Note that the BKI_DEFAULT values below are only used for rows describing
 * BKI_BOOTSTRAP catalogs, since only those rows appear in pg_class.dat.
 * ----------------
 */
CATALOG(pg_class,1259,RelationRelationId) BKI_BOOTSTRAP BKI_ROWTYPE_OID(83,RelationRelation_Rowtype_Id) BKI_SCHEMA_MACRO
{
    /* oid */
    Oid         oid;

    /* class name */
    NameData    relname;

    /* OID of namespace containing this class */
    Oid         relnamespace BKI_DEFAULT(PGNSP);

    /* OID of entry in pg_type for table's implicit row type */
    Oid         reltype BKI_LOOKUP(pg_type);

    /* OID of entry in pg_type for underlying composite type */
    Oid         reloftype BKI_DEFAULT(0) BKI_LOOKUP(pg_type);

    /* class owner */
    Oid         relowner BKI_DEFAULT(PGUID);

    /* access method; 0 if not a table / index */
    Oid         relam BKI_DEFAULT(heap) BKI_LOOKUP(pg_am);

    /* identifier of physical storage file */
    /* relfilenode == 0 means it is a "mapped" relation, see relmapper.c */
    Oid         relfilenode BKI_DEFAULT(0);

    /* identifier of table space for relation (0 means default for database) */
    Oid         reltablespace BKI_DEFAULT(0) BKI_LOOKUP(pg_tablespace);

    /* # of blocks (not always up-to-date) */
    int32       relpages BKI_DEFAULT(0);

    /* # of tuples (not always up-to-date) */
    float4      reltuples BKI_DEFAULT(0);

    /* # of all-visible blocks (not always up-to-date) */
    int32       relallvisible BKI_DEFAULT(0);

    /* OID of toast table; 0 if none */
    Oid         reltoastrelid BKI_DEFAULT(0);

    /* T if has (or has had) any indexes */
    bool        relhasindex BKI_DEFAULT(f);

    /* T if shared across databases */
    bool        relisshared BKI_DEFAULT(f);

    /* see RELPERSISTENCE_xxx constants below */
    char        relpersistence BKI_DEFAULT(p);

    /* see RELKIND_xxx constants below */
    char        relkind BKI_DEFAULT(r);

    /* number of user attributes */
    int16       relnatts BKI_DEFAULT(0);    /* genbki.pl will fill this in */

    /*
     * Class pg_attribute must contain exactly "relnatts" user attributes
     * (with attnums ranging from 1 to relnatts) for this class.  It may also
     * contain entries with negative attnums for system attributes.
     */

    /* # of CHECK constraints for class */
    int16       relchecks BKI_DEFAULT(0);

    /* has (or has had) any rules */
    bool        relhasrules BKI_DEFAULT(f);

    /* has (or has had) any TRIGGERs */
    bool        relhastriggers BKI_DEFAULT(f);

    /* has (or has had) child tables or indexes */
    bool        relhassubclass BKI_DEFAULT(f);

    /* row security is enabled or not */
    bool        relrowsecurity BKI_DEFAULT(f);

    /* row security forced for owners or not */
    bool        relforcerowsecurity BKI_DEFAULT(f);

    /* matview currently holds query results */
    bool        relispopulated BKI_DEFAULT(t);

    /* see REPLICA_IDENTITY_xxx constants */
    char        relreplident BKI_DEFAULT(n);

    /* is relation a partition? */
    bool        relispartition BKI_DEFAULT(f);

    /* heap for rewrite during DDL, link to original rel */
    Oid         relrewrite BKI_DEFAULT(0);

    /* all Xids < this are frozen in this rel */
    TransactionId relfrozenxid BKI_DEFAULT(3);  /* FirstNormalTransactionId */

    /* all multixacts in this rel are >= this; it is really a MultiXactId */
    TransactionId relminmxid BKI_DEFAULT(1);    /* FirstMultiXactId */

#ifdef CATALOG_VARLEN           /* variable-length fields start here */
    /* NOTE: These fields are not present in a relcache entry's rd_rel field. */
    /* access permissions */
    aclitem     relacl[1] BKI_DEFAULT(_null_);

    /* access-method-specific options */
    text        reloptions[1] BKI_DEFAULT(_null_);

    /* partition bound node tree */
    pg_node_tree relpartbound BKI_DEFAULT(_null_);
#endif
} FormData_pg_class;

/* Size of fixed part of pg_class tuples, not counting var-length fields */
#define CLASS_TUPLE_SIZE \
     (offsetof(FormData_pg_class,relminmxid) + sizeof(TransactionId))

/* ----------------
 *      Form_pg_class corresponds to a pointer to a tuple with
 *      the format of pg_class relation.
 * ----------------
 */
typedef FormData_pg_class *Form_pg_class;

#ifdef EXPOSE_TO_CLIENT_CODE

#define       RELKIND_RELATION        'r'   /* ordinary table */
#define       RELKIND_INDEX           'i'   /* secondary index */
#define       RELKIND_SEQUENCE        'S'   /* sequence object */
#define       RELKIND_TOASTVALUE      't'   /* for out-of-line values */
#define       RELKIND_VIEW            'v'   /* view */
#define       RELKIND_MATVIEW         'm'   /* materialized view */
#define       RELKIND_COMPOSITE_TYPE  'c'   /* composite type */
#define       RELKIND_FOREIGN_TABLE   'f'   /* foreign table */
#define       RELKIND_PARTITIONED_TABLE 'p' /* partitioned table */
#define       RELKIND_PARTITIONED_INDEX 'I' /* partitioned index */

#define       RELPERSISTENCE_PERMANENT  'p' /* regular table */
#define       RELPERSISTENCE_UNLOGGED   'u' /* unlogged permanent table */
#define       RELPERSISTENCE_TEMP       't' /* temporary table */

/* default selection for replica identity (primary key or nothing) */
#define       REPLICA_IDENTITY_DEFAULT  'd'
/* no replica identity is logged for this relation */
#define       REPLICA_IDENTITY_NOTHING  'n'
/* all columns are logged as replica identity */
#define       REPLICA_IDENTITY_FULL     'f'
/*
 * an explicitly chosen candidate key's columns are used as replica identity.
 * Note this will still be set if the index has been dropped; in that case it
 * has the same meaning as 'd'.
 */
#define       REPLICA_IDENTITY_INDEX    'i'

/*
 * Relation kinds that have physical storage. These relations normally have
 * relfilenode set to non-zero, but it can also be zero if the relation is
 * mapped.
 */
#define RELKIND_HAS_STORAGE(relkind) \
    ((relkind) == RELKIND_RELATION || \
     (relkind) == RELKIND_INDEX || \
     (relkind) == RELKIND_SEQUENCE || \
     (relkind) == RELKIND_TOASTVALUE || \
     (relkind) == RELKIND_MATVIEW)


#endif                          /* EXPOSE_TO_CLIENT_CODE */

#endif                          /* PG_CLASS_H */