genam.c File Reference

#include "postgres.h"
#include "access/genam.h"
#include "access/heapam.h"
#include "access/relscan.h"
#include "access/tableam.h"
#include "access/transam.h"
#include "catalog/index.h"
#include "lib/stringinfo.h"
#include "miscadmin.h"
#include "storage/bufmgr.h"
#include "storage/procarray.h"
#include "utils/acl.h"
#include "utils/injection_point.h"
#include "utils/lsyscache.h"
#include "utils/rel.h"
#include "utils/rls.h"
#include "utils/ruleutils.h"
#include "utils/snapmgr.h"

Include dependency graph for genam.c:

Go to the source code of this file.

Functions
IndexScanDesc	RelationGetIndexScan (Relation indexRelation, int nkeys, int norderbys)
void	IndexScanEnd (IndexScanDesc scan)
char *	BuildIndexValueDescription (Relation indexRelation, const Datum *values, const bool *isnull)
TransactionId	index_compute_xid_horizon_for_tuples (Relation irel, Relation hrel, Buffer ibuf, OffsetNumber *itemnos, int nitems)
SysScanDesc	systable_beginscan (Relation heapRelation, Oid indexId, bool indexOK, Snapshot snapshot, int nkeys, ScanKey key)
static void	HandleConcurrentAbort ()
HeapTuple	systable_getnext (SysScanDesc sysscan)
bool	systable_recheck_tuple (SysScanDesc sysscan, HeapTuple tup)
void	systable_endscan (SysScanDesc sysscan)
SysScanDesc	systable_beginscan_ordered (Relation heapRelation, Relation indexRelation, Snapshot snapshot, int nkeys, ScanKey key)
HeapTuple	systable_getnext_ordered (SysScanDesc sysscan, ScanDirection direction)
void	systable_endscan_ordered (SysScanDesc sysscan)
void	systable_inplace_update_begin (Relation relation, Oid indexId, bool indexOK, Snapshot snapshot, int nkeys, const ScanKeyData *key, HeapTuple *oldtupcopy, void **state)
void	systable_inplace_update_finish (void *state, HeapTuple tuple)
void	systable_inplace_update_cancel (void *state)

Function Documentation

BuildIndexValueDescription()

char * BuildIndexValueDescription	(	Relation	indexRelation,
		const Datum *	values,
		const bool *	isnull
	)

Definition at line 178 of file genam.c.

{
    StringInfoData buf;
    Form_pg_index idxrec;
    int         indnkeyatts;
    int         i;
    int         keyno;
    Oid         indexrelid = RelationGetRelid(indexRelation);
    Oid         indrelid;
    AclResult   aclresult;
 
    indnkeyatts = IndexRelationGetNumberOfKeyAttributes(indexRelation);
 
    /*
     * Check permissions- if the user does not have access to view all of the
     * key columns then return NULL to avoid leaking data.
     *
     * First check if RLS is enabled for the relation.  If so, return NULL to
     * avoid leaking data.
     *
     * Next we need to check table-level SELECT access and then, if there is
     * no access there, check column-level permissions.
     */
    idxrec = indexRelation->rd_index;
    indrelid = idxrec->indrelid;
    Assert(indexrelid == idxrec->indexrelid);
 
    /* RLS check- if RLS is enabled then we don't return anything. */
    if (check_enable_rls(indrelid, InvalidOid, true) == RLS_ENABLED)
        return NULL;
 
    /* Table-level SELECT is enough, if the user has it */
    aclresult = pg_class_aclcheck(indrelid, GetUserId(), ACL_SELECT);
    if (aclresult != ACLCHECK_OK)
    {
        /*
         * No table-level access, so step through the columns in the index and
         * make sure the user has SELECT rights on all of them.
         */
        for (keyno = 0; keyno < indnkeyatts; keyno++)
        {
            AttrNumber  attnum = idxrec->indkey.values[keyno];
 
            /*
             * Note that if attnum == InvalidAttrNumber, then this is an index
             * based on an expression and we return no detail rather than try
             * to figure out what column(s) the expression includes and if the
             * user has SELECT rights on them.
             */
            if (attnum == InvalidAttrNumber ||
                pg_attribute_aclcheck(indrelid, attnum, GetUserId(),
                                      ACL_SELECT) != ACLCHECK_OK)
            {
                /* No access, so clean up and return */
                return NULL;
            }
        }
    }
 
    initStringInfo(&buf);
    appendStringInfo(&buf, "(%s)=(",
                     pg_get_indexdef_columns(indexrelid, true));
 
    for (i = 0; i < indnkeyatts; i++)
    {
        char       *val;
 
        if (isnull[i])
            val = "null";
        else
        {
            Oid         foutoid;
            bool        typisvarlena;
 
            /*
             * The provided data is not necessarily of the type stored in the
             * index; rather it is of the index opclass's input type. So look
             * at rd_opcintype not the index tupdesc.
             *
             * Note: this is a bit shaky for opclasses that have pseudotype
             * input types such as ANYARRAY or RECORD.  Currently, the
             * typoutput functions associated with the pseudotypes will work
             * okay, but we might have to try harder in future.
             */
            getTypeOutputInfo(indexRelation->rd_opcintype[i],
                              &foutoid, &typisvarlena);
            val = OidOutputFunctionCall(foutoid, values[i]);
        }
 
        if (i > 0)
            appendStringInfoString(&buf, ", ");
        appendStringInfoString(&buf, val);
    }
 
    appendStringInfoChar(&buf, ')');
 
    return buf.data;
}

References ACL_SELECT, ACLCHECK_OK, appendStringInfo(), appendStringInfoChar(), appendStringInfoString(), Assert(), attnum, buf, check_enable_rls(), getTypeOutputInfo(), GetUserId(), i, IndexRelationGetNumberOfKeyAttributes, initStringInfo(), InvalidAttrNumber, InvalidOid, OidOutputFunctionCall(), pg_attribute_aclcheck(), pg_class_aclcheck(), pg_get_indexdef_columns(), RelationData::rd_index, RelationData::rd_opcintype, RelationGetRelid, RLS_ENABLED, val, and values.

Referenced by _bt_check_unique(), build_index_value_desc(), check_exclusion_or_unique_constraint(), and comparetup_index_btree_tiebreak().

HandleConcurrentAbort()

static void HandleConcurrentAbort ( )

inlinestatic

Definition at line 491 of file genam.c.

{
    if (TransactionIdIsValid(CheckXidAlive) &&
        !TransactionIdIsInProgress(CheckXidAlive) &&
        !TransactionIdDidCommit(CheckXidAlive))
        ereport(ERROR,
                (errcode(ERRCODE_TRANSACTION_ROLLBACK),
                 errmsg("transaction aborted during system catalog scan")));
}

References CheckXidAlive, ereport, errcode(), errmsg(), ERROR, TransactionIdDidCommit(), TransactionIdIsInProgress(), and TransactionIdIsValid.

Referenced by systable_getnext(), systable_getnext_ordered(), and systable_recheck_tuple().

index_compute_xid_horizon_for_tuples()

TransactionId index_compute_xid_horizon_for_tuples	(	Relation	irel,
		Relation	hrel,
		Buffer	ibuf,
		OffsetNumber *	itemnos,
		int	nitems
	)

Definition at line 295 of file genam.c.

{
    TM_IndexDeleteOp delstate;
    TransactionId snapshotConflictHorizon = InvalidTransactionId;
    Page        ipage = BufferGetPage(ibuf);
    IndexTuple  itup;
 
    Assert(nitems > 0);
 
    delstate.irel = irel;
    delstate.iblknum = BufferGetBlockNumber(ibuf);
    delstate.bottomup = false;
    delstate.bottomupfreespace = 0;
    delstate.ndeltids = 0;
    delstate.deltids = palloc(nitems * sizeof(TM_IndexDelete));
    delstate.status = palloc(nitems * sizeof(TM_IndexStatus));
 
    /* identify what the index tuples about to be deleted point to */
    for (int i = 0; i < nitems; i++)
    {
        OffsetNumber offnum = itemnos[i];
        ItemId      iitemid;
 
        iitemid = PageGetItemId(ipage, offnum);
        itup = (IndexTuple) PageGetItem(ipage, iitemid);
 
        Assert(ItemIdIsDead(iitemid));
 
        ItemPointerCopy(&itup->t_tid, &delstate.deltids[i].tid);
        delstate.deltids[i].id = delstate.ndeltids;
        delstate.status[i].idxoffnum = offnum;
        delstate.status[i].knowndeletable = true;   /* LP_DEAD-marked */
        delstate.status[i].promising = false;   /* unused */
        delstate.status[i].freespace = 0;   /* unused */
 
        delstate.ndeltids++;
    }
 
    /* determine the actual xid horizon */
    snapshotConflictHorizon = table_index_delete_tuples(hrel, &delstate);
 
    /* assert tableam agrees that all items are deletable */
    Assert(delstate.ndeltids == nitems);
 
    pfree(delstate.deltids);
    pfree(delstate.status);
 
    return snapshotConflictHorizon;
}

References Assert(), TM_IndexDeleteOp::bottomup, TM_IndexDeleteOp::bottomupfreespace, BufferGetBlockNumber(), BufferGetPage(), TM_IndexDeleteOp::deltids, TM_IndexStatus::freespace, i, TM_IndexDeleteOp::iblknum, TM_IndexDelete::id, TM_IndexStatus::idxoffnum, InvalidTransactionId, TM_IndexDeleteOp::irel, ItemIdIsDead, ItemPointerCopy(), TM_IndexStatus::knowndeletable, TM_IndexDeleteOp::ndeltids, nitems, PageGetItem(), PageGetItemId(), palloc(), pfree(), TM_IndexStatus::promising, TM_IndexDeleteOp::status, IndexTupleData::t_tid, table_index_delete_tuples(), and TM_IndexDelete::tid.

Referenced by _hash_vacuum_one_page(), and gistprunepage().

IndexScanEnd()

void IndexScanEnd

(

IndexScanDesc

scan

)

Definition at line 145 of file genam.c.

{
    if (scan->keyData != NULL)
        pfree(scan->keyData);
    if (scan->orderByData != NULL)
        pfree(scan->orderByData);
 
    pfree(scan);
}

References IndexScanDescData::keyData, IndexScanDescData::orderByData, and pfree().

Referenced by index_endscan().

RelationGetIndexScan()

IndexScanDesc RelationGetIndexScan	(	Relation	indexRelation,
		int	nkeys,
		int	norderbys
	)

Definition at line 80 of file genam.c.

{
    IndexScanDesc scan;
 
    scan = (IndexScanDesc) palloc(sizeof(IndexScanDescData));
 
    scan->heapRelation = NULL;  /* may be set later */
    scan->xs_heapfetch = NULL;
    scan->indexRelation = indexRelation;
    scan->xs_snapshot = InvalidSnapshot;    /* caller must initialize this */
    scan->numberOfKeys = nkeys;
    scan->numberOfOrderBys = norderbys;
 
    /*
     * We allocate key workspace here, but it won't get filled until amrescan.
     */
    if (nkeys > 0)
        scan->keyData = (ScanKey) palloc(sizeof(ScanKeyData) * nkeys);
    else
        scan->keyData = NULL;
    if (norderbys > 0)
        scan->orderByData = (ScanKey) palloc(sizeof(ScanKeyData) * norderbys);
    else
        scan->orderByData = NULL;
 
    scan->xs_want_itup = false; /* may be set later */
 
    /*
     * During recovery we ignore killed tuples and don't bother to kill them
     * either. We do this because the xmin on the primary node could easily be
     * later than the xmin on the standby node, so that what the primary
     * thinks is killed is supposed to be visible on standby. So for correct
     * MVCC for queries during recovery we must ignore these hints and check
     * all tuples. Do *not* set ignore_killed_tuples to true when running in a
     * transaction that was started during recovery. xactStartedInRecovery
     * should not be altered by index AMs.
     */
    scan->kill_prior_tuple = false;
    scan->xactStartedInRecovery = TransactionStartedDuringRecovery();
    scan->ignore_killed_tuples = !scan->xactStartedInRecovery;
 
    scan->opaque = NULL;
    scan->instrument = NULL;
 
    scan->xs_itup = NULL;
    scan->xs_itupdesc = NULL;
    scan->xs_hitup = NULL;
    scan->xs_hitupdesc = NULL;
 
    return scan;
}

References IndexScanDescData::heapRelation, IndexScanDescData::ignore_killed_tuples, IndexScanDescData::indexRelation, IndexScanDescData::instrument, InvalidSnapshot, IndexScanDescData::keyData, IndexScanDescData::kill_prior_tuple, IndexScanDescData::numberOfKeys, IndexScanDescData::numberOfOrderBys, IndexScanDescData::opaque, IndexScanDescData::orderByData, palloc(), TransactionStartedDuringRecovery(), IndexScanDescData::xactStartedInRecovery, IndexScanDescData::xs_heapfetch, IndexScanDescData::xs_hitup, IndexScanDescData::xs_hitupdesc, IndexScanDescData::xs_itup, IndexScanDescData::xs_itupdesc, IndexScanDescData::xs_snapshot, and IndexScanDescData::xs_want_itup.

Referenced by blbeginscan(), brinbeginscan(), btbeginscan(), dibeginscan(), ginbeginscan(), gistbeginscan(), hashbeginscan(), and spgbeginscan().

systable_beginscan()

SysScanDesc systable_beginscan	(	Relation	heapRelation,
		Oid	indexId,
		bool	indexOK,
		Snapshot	snapshot,
		int	nkeys,
		ScanKey	key
	)

Definition at line 388 of file genam.c.

{
    SysScanDesc sysscan;
    Relation    irel;
 
    if (indexOK &&
        !IgnoreSystemIndexes &&
        !ReindexIsProcessingIndex(indexId))
        irel = index_open(indexId, AccessShareLock);
    else
        irel = NULL;
 
    sysscan = (SysScanDesc) palloc(sizeof(SysScanDescData));
 
    sysscan->heap_rel = heapRelation;
    sysscan->irel = irel;
    sysscan->slot = table_slot_create(heapRelation, NULL);
 
    if (snapshot == NULL)
    {
        Oid         relid = RelationGetRelid(heapRelation);
 
        snapshot = RegisterSnapshot(GetCatalogSnapshot(relid));
        sysscan->snapshot = snapshot;
    }
    else
    {
        /* Caller is responsible for any snapshot. */
        sysscan->snapshot = NULL;
    }
 
    if (irel)
    {
        int         i;
        ScanKey     idxkey;
 
        idxkey = palloc_array(ScanKeyData, nkeys);
 
        /* Convert attribute numbers to be index column numbers. */
        for (i = 0; i < nkeys; i++)
        {
            int         j;
 
            memcpy(&idxkey[i], &key[i], sizeof(ScanKeyData));
 
            for (j = 0; j < IndexRelationGetNumberOfAttributes(irel); j++)
            {
                if (key[i].sk_attno == irel->rd_index->indkey.values[j])
                {
                    idxkey[i].sk_attno = j + 1;
                    break;
                }
            }
            if (j == IndexRelationGetNumberOfAttributes(irel))
                elog(ERROR, "column is not in index");
        }
 
        sysscan->iscan = index_beginscan(heapRelation, irel,
                                         snapshot, NULL, nkeys, 0);
        index_rescan(sysscan->iscan, idxkey, nkeys, NULL, 0);
        sysscan->scan = NULL;
 
        pfree(idxkey);
    }
    else
    {
        /*
         * We disallow synchronized scans when forced to use a heapscan on a
         * catalog.  In most cases the desired rows are near the front, so
         * that the unpredictable start point of a syncscan is a serious
         * disadvantage; and there are no compensating advantages, because
         * it's unlikely that such scans will occur in parallel.
         */
        sysscan->scan = table_beginscan_strat(heapRelation, snapshot,
                                              nkeys, key,
                                              true, false);
        sysscan->iscan = NULL;
    }
 
    /*
     * If CheckXidAlive is set then set a flag to indicate that system table
     * scan is in-progress.  See detailed comments in xact.c where these
     * variables are declared.
     */
    if (TransactionIdIsValid(CheckXidAlive))
        bsysscan = true;
 
    return sysscan;
}

References AccessShareLock, bsysscan, CheckXidAlive, elog, ERROR, GetCatalogSnapshot(), SysScanDescData::heap_rel, i, IgnoreSystemIndexes, index_beginscan(), index_open(), index_rescan(), IndexRelationGetNumberOfAttributes, SysScanDescData::irel, SysScanDescData::iscan, j, sort-test::key, palloc(), palloc_array, pfree(), RelationData::rd_index, RegisterSnapshot(), ReindexIsProcessingIndex(), RelationGetRelid, SysScanDescData::scan, ScanKeyData::sk_attno, SysScanDescData::slot, SysScanDescData::snapshot, table_beginscan_strat(), table_slot_create(), and TransactionIdIsValid.

Referenced by AfterTriggerSetState(), AlterConstraintNamespaces(), AlterConstrDeferrabilityRecurse(), AlterConstrEnforceabilityRecurse(), AlterConstrTriggerDeferrability(), AlterDatabase(), AlterDatabaseOwner(), AlterDatabaseRefreshColl(), AlterDomainDropConstraint(), AlterDomainValidateConstraint(), AlterExtensionNamespace(), AlterPolicy(), AlterSeqNamespaces(), AlterSetting(), AlterTypeRecurse(), ApplyExtensionUpdates(), ApplySetting(), ATExecAddOf(), ATExecAlterColumnType(), ATExecAlterConstraint(), ATExecAttachPartition(), ATExecDropConstraint(), ATExecValidateConstraint(), ATPrepChangePersistence(), AttrDefaultFetch(), change_owner_fix_column_acls(), change_owner_recurse_to_sequences(), changeDependenciesOf(), changeDependenciesOn(), changeDependencyFor(), CheckNNConstraintFetch(), checkSharedDependencies(), ChooseConstraintName(), CloneFkReferenced(), CloneRowTriggersToPartition(), ConstraintNameExists(), ConstraintNameIsUsed(), CopyStatistics(), copyTemplateDependencies(), CountDBSubscriptions(), CreateComments(), CreateInheritance(), CreatePolicy(), CreateSharedComments(), CreateTriggerFiringOn(), DefineOpClass(), DefineTSConfiguration(), DeleteAttributeTuples(), DeleteComments(), deleteDependencyRecordsFor(), deleteDependencyRecordsForClass(), deleteDependencyRecordsForSpecific(), DeleteInheritsTuple(), DeleteInitPrivs(), deleteOneObject(), DeleteSecurityLabel(), DeleteSharedComments(), DeleteSharedSecurityLabel(), DeleteSystemAttributeTuples(), drop_parent_dependency(), DropClonedTriggersFromPartition(), DropConfigurationMapping(), dropconstraint_internal(), dropDatabaseDependencies(), DropForeignKeyConstraintTriggers(), DropObjectById(), DropRole(), EnableDisableTrigger(), EnumValuesDelete(), exec_object_restorecon(), ExecAlterExtensionStmt(), ExecGrant_Largeobject(), extension_config_remove(), fetch_statentries_for_relation(), find_composite_type_dependencies(), find_inheritance_children_extended(), findDependentObjects(), findDomainNotNullConstraint(), findNotNullConstraintAttnum(), get_catalog_object_by_oid_extended(), get_database_oid(), get_db_info(), get_domain_constraint_oid(), get_index_constraint(), get_index_ref_constraints(), get_partition_parent_worker(), get_pkey_attnames(), get_primary_key_attnos(), get_relation_constraint_attnos(), get_relation_constraint_oid(), get_relation_idx_constraint_oid(), get_relation_policy_oid(), get_rels_with_domain(), get_trigger_oid(), GetAllTablesPublications(), GetAttrDefaultColumnAddress(), GetAttrDefaultOid(), getAutoExtensionsOfObject(), GetComment(), GetDatabaseTuple(), GetDatabaseTupleByOid(), GetDefaultOpClass(), getExtensionOfObject(), GetForeignKeyActionTriggers(), GetForeignKeyCheckTriggers(), GetNewOidWithIndex(), getObjectDescription(), getObjectIdentityParts(), getOwnedSequences_internal(), GetParentedForeignKeyRefs(), GetPublicationRelations(), GetPublicationSchemas(), GetSecurityLabel(), GetSharedSecurityLabel(), GetSubscriptionRelations(), has_superclass(), HasSubscriptionRelations(), heap_truncate_find_FKs(), index_concurrently_swap(), IndexSetParentIndex(), is_schema_publication(), LargeObjectDrop(), LargeObjectExistsWithSnapshot(), load_domaintype_info(), load_enum_cache_data(), LookupOpclassInfo(), makeConfigurationDependencies(), MakeConfigurationMapping(), MarkInheritDetached(), MergeConstraintsIntoExisting(), MergeWithExistingConstraint(), movedb(), object_ownercheck(), PartitionHasPendingDetach(), pg_extension_config_dump(), pg_get_constraintdef_worker(), pg_get_serial_sequence(), pg_get_triggerdef_worker(), pg_largeobject_aclmask_snapshot(), QueueFKConstraintValidation(), RangeDelete(), recordExtensionInitPrivWorker(), recordExtObjInitPriv(), relation_has_policies(), RelationBuildPartitionDesc(), RelationBuildRowSecurity(), RelationBuildRuleLock(), RelationBuildTriggers(), RelationBuildTupleDesc(), RelationGetExclusionInfo(), RelationGetFKeyList(), RelationGetIndexList(), RelationGetNotNullConstraints(), RelationGetStatExtList(), RelationRemoveInheritance(), RelidByRelfilenumber(), RememberAllDependentForRebuilding(), RemoveAttrDefault(), RemoveAttrDefaultById(), RemoveExtensionById(), RemoveInheritance(), RemoveInheritedConstraint(), RemovePolicyById(), RemoveRewriteRuleById(), RemoveRoleFromInitPriv(), RemoveRoleFromObjectACL(), RemoveRoleFromObjectPolicy(), RemoveStatistics(), RemoveTriggerById(), RemoveTSConfigurationById(), rename_policy(), renametrig(), renametrig_internal(), renametrig_partition(), ReplaceRoleInInitPriv(), replorigin_create(), ScanPgRelation(), SearchCatCacheList(), SearchCatCacheMiss(), sepgsql_attribute_post_create(), sepgsql_database_post_create(), sepgsql_proc_post_create(), sepgsql_proc_setattr(), sepgsql_relation_post_create(), sepgsql_relation_setattr(), sepgsql_relation_setattr_extra(), sepgsql_schema_post_create(), sequenceIsOwned(), SetSecurityLabel(), SetSharedSecurityLabel(), shdepChangeDep(), shdepDropDependency(), shdepDropOwned(), shdepReassignOwned(), systable_inplace_update_begin(), toastrel_valueid_exists(), TriggerSetParentTrigger(), typeInheritsFrom(), vac_update_datfrozenxid(), and validatePartitionedIndex().

systable_beginscan_ordered()

SysScanDesc systable_beginscan_ordered	(	Relation	heapRelation,
		Relation	indexRelation,
		Snapshot	snapshot,
		int	nkeys,
		ScanKey	key
	)

Definition at line 650 of file genam.c.

{
    SysScanDesc sysscan;
    int         i;
    ScanKey     idxkey;
 
    /* REINDEX can probably be a hard error here ... */
    if (ReindexIsProcessingIndex(RelationGetRelid(indexRelation)))
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("cannot access index \"%s\" while it is being reindexed",
                        RelationGetRelationName(indexRelation))));
    /* ... but we only throw a warning about violating IgnoreSystemIndexes */
    if (IgnoreSystemIndexes)
        elog(WARNING, "using index \"%s\" despite IgnoreSystemIndexes",
             RelationGetRelationName(indexRelation));
 
    sysscan = (SysScanDesc) palloc(sizeof(SysScanDescData));
 
    sysscan->heap_rel = heapRelation;
    sysscan->irel = indexRelation;
    sysscan->slot = table_slot_create(heapRelation, NULL);
 
    if (snapshot == NULL)
    {
        Oid         relid = RelationGetRelid(heapRelation);
 
        snapshot = RegisterSnapshot(GetCatalogSnapshot(relid));
        sysscan->snapshot = snapshot;
    }
    else
    {
        /* Caller is responsible for any snapshot. */
        sysscan->snapshot = NULL;
    }
 
    idxkey = palloc_array(ScanKeyData, nkeys);
 
    /* Convert attribute numbers to be index column numbers. */
    for (i = 0; i < nkeys; i++)
    {
        int         j;
 
        memcpy(&idxkey[i], &key[i], sizeof(ScanKeyData));
 
        for (j = 0; j < IndexRelationGetNumberOfAttributes(indexRelation); j++)
        {
            if (key[i].sk_attno == indexRelation->rd_index->indkey.values[j])
            {
                idxkey[i].sk_attno = j + 1;
                break;
            }
        }
        if (j == IndexRelationGetNumberOfAttributes(indexRelation))
            elog(ERROR, "column is not in index");
    }
 
    sysscan->iscan = index_beginscan(heapRelation, indexRelation,
                                     snapshot, NULL, nkeys, 0);
    index_rescan(sysscan->iscan, idxkey, nkeys, NULL, 0);
    sysscan->scan = NULL;
 
    pfree(idxkey);
 
    /*
     * If CheckXidAlive is set then set a flag to indicate that system table
     * scan is in-progress.  See detailed comments in xact.c where these
     * variables are declared.
     */
    if (TransactionIdIsValid(CheckXidAlive))
        bsysscan = true;
 
    return sysscan;
}

References bsysscan, CheckXidAlive, elog, ereport, errcode(), errmsg(), ERROR, GetCatalogSnapshot(), SysScanDescData::heap_rel, i, IgnoreSystemIndexes, index_beginscan(), index_rescan(), IndexRelationGetNumberOfAttributes, SysScanDescData::irel, SysScanDescData::iscan, j, sort-test::key, palloc(), palloc_array, pfree(), RelationData::rd_index, RegisterSnapshot(), ReindexIsProcessingIndex(), RelationGetRelationName, RelationGetRelid, SysScanDescData::scan, ScanKeyData::sk_attno, SysScanDescData::slot, SysScanDescData::snapshot, table_slot_create(), TransactionIdIsValid, and WARNING.

Referenced by BuildEventTriggerCache(), check_toasted_attribute(), enum_endpoint(), enum_range_internal(), heap_fetch_toast_slice(), inv_getsize(), inv_read(), inv_truncate(), inv_write(), lookup_ts_config_cache(), and toast_delete_datum().

systable_endscan()

void systable_endscan

(

SysScanDesc

sysscan

)

Definition at line 603 of file genam.c.

{
    if (sysscan->slot)
    {
        ExecDropSingleTupleTableSlot(sysscan->slot);
        sysscan->slot = NULL;
    }
 
    if (sysscan->irel)
    {
        index_endscan(sysscan->iscan);
        index_close(sysscan->irel, AccessShareLock);
    }
    else
        table_endscan(sysscan->scan);
 
    if (sysscan->snapshot)
        UnregisterSnapshot(sysscan->snapshot);
 
    /*
     * Reset the bsysscan flag at the end of the systable scan.  See detailed
     * comments in xact.c where these variables are declared.
     */
    if (TransactionIdIsValid(CheckXidAlive))
        bsysscan = false;
 
    pfree(sysscan);
}

References AccessShareLock, bsysscan, CheckXidAlive, ExecDropSingleTupleTableSlot(), index_close(), index_endscan(), SysScanDescData::irel, SysScanDescData::iscan, pfree(), SysScanDescData::scan, SysScanDescData::slot, SysScanDescData::snapshot, table_endscan(), TransactionIdIsValid, and UnregisterSnapshot().

Referenced by AfterTriggerSetState(), AlterConstraintNamespaces(), AlterConstrDeferrabilityRecurse(), AlterConstrEnforceabilityRecurse(), AlterConstrTriggerDeferrability(), AlterDatabase(), AlterDatabaseOwner(), AlterDatabaseRefreshColl(), AlterDomainDropConstraint(), AlterDomainValidateConstraint(), AlterExtensionNamespace(), AlterPolicy(), AlterSeqNamespaces(), AlterSetting(), AlterTypeRecurse(), ApplyExtensionUpdates(), ApplySetting(), ATExecAddOf(), ATExecAlterColumnType(), ATExecAlterConstraint(), ATExecAttachPartition(), ATExecDropConstraint(), ATExecValidateConstraint(), ATPrepChangePersistence(), AttrDefaultFetch(), change_owner_fix_column_acls(), change_owner_recurse_to_sequences(), changeDependenciesOf(), changeDependenciesOn(), changeDependencyFor(), CheckNNConstraintFetch(), checkSharedDependencies(), ChooseConstraintName(), CloneFkReferenced(), CloneRowTriggersToPartition(), ConstraintNameExists(), ConstraintNameIsUsed(), CopyStatistics(), copyTemplateDependencies(), CountDBSubscriptions(), CreateComments(), CreateInheritance(), CreatePolicy(), CreateSharedComments(), CreateTriggerFiringOn(), DefineOpClass(), DefineTSConfiguration(), DeleteAttributeTuples(), DeleteComments(), deleteDependencyRecordsFor(), deleteDependencyRecordsForClass(), deleteDependencyRecordsForSpecific(), DeleteInheritsTuple(), DeleteInitPrivs(), deleteOneObject(), DeleteSecurityLabel(), DeleteSharedComments(), DeleteSharedSecurityLabel(), DeleteSystemAttributeTuples(), drop_parent_dependency(), DropClonedTriggersFromPartition(), DropConfigurationMapping(), dropconstraint_internal(), dropDatabaseDependencies(), DropForeignKeyConstraintTriggers(), DropObjectById(), DropRole(), EnableDisableTrigger(), EnumValuesDelete(), exec_object_restorecon(), ExecAlterExtensionStmt(), ExecGrant_Largeobject(), extension_config_remove(), fetch_statentries_for_relation(), find_composite_type_dependencies(), find_inheritance_children_extended(), findDependentObjects(), findDomainNotNullConstraint(), findNotNullConstraintAttnum(), get_catalog_object_by_oid_extended(), get_database_oid(), get_db_info(), get_domain_constraint_oid(), get_index_constraint(), get_index_ref_constraints(), get_partition_parent_worker(), get_pkey_attnames(), get_primary_key_attnos(), get_relation_constraint_attnos(), get_relation_constraint_oid(), get_relation_idx_constraint_oid(), get_relation_policy_oid(), get_rels_with_domain(), get_trigger_oid(), GetAllTablesPublications(), GetAttrDefaultColumnAddress(), GetAttrDefaultOid(), getAutoExtensionsOfObject(), GetComment(), GetDatabaseTuple(), GetDatabaseTupleByOid(), GetDefaultOpClass(), getExtensionOfObject(), GetForeignKeyActionTriggers(), GetForeignKeyCheckTriggers(), GetNewOidWithIndex(), getObjectDescription(), getObjectIdentityParts(), getOwnedSequences_internal(), GetParentedForeignKeyRefs(), GetPublicationRelations(), GetPublicationSchemas(), GetSecurityLabel(), GetSharedSecurityLabel(), GetSubscriptionRelations(), has_superclass(), HasSubscriptionRelations(), heap_truncate_find_FKs(), index_concurrently_swap(), IndexSetParentIndex(), is_schema_publication(), LargeObjectDrop(), LargeObjectExistsWithSnapshot(), load_domaintype_info(), load_enum_cache_data(), LookupOpclassInfo(), makeConfigurationDependencies(), MakeConfigurationMapping(), MarkInheritDetached(), MergeConstraintsIntoExisting(), MergeWithExistingConstraint(), movedb(), object_ownercheck(), PartitionHasPendingDetach(), pg_extension_config_dump(), pg_get_constraintdef_worker(), pg_get_serial_sequence(), pg_get_triggerdef_worker(), pg_largeobject_aclmask_snapshot(), QueueFKConstraintValidation(), RangeDelete(), recordExtensionInitPrivWorker(), recordExtObjInitPriv(), relation_has_policies(), RelationBuildPartitionDesc(), RelationBuildRowSecurity(), RelationBuildRuleLock(), RelationBuildTriggers(), RelationBuildTupleDesc(), RelationGetExclusionInfo(), RelationGetFKeyList(), RelationGetIndexList(), RelationGetNotNullConstraints(), RelationGetStatExtList(), RelationRemoveInheritance(), RelidByRelfilenumber(), RememberAllDependentForRebuilding(), RemoveAttrDefault(), RemoveAttrDefaultById(), RemoveExtensionById(), RemoveInheritance(), RemoveInheritedConstraint(), RemovePolicyById(), RemoveRewriteRuleById(), RemoveRoleFromInitPriv(), RemoveRoleFromObjectACL(), RemoveRoleFromObjectPolicy(), RemoveStatistics(), RemoveTriggerById(), RemoveTSConfigurationById(), rename_policy(), renametrig(), renametrig_internal(), renametrig_partition(), ReplaceRoleInInitPriv(), replorigin_create(), ScanPgRelation(), SearchCatCacheList(), SearchCatCacheMiss(), sepgsql_attribute_post_create(), sepgsql_database_post_create(), sepgsql_proc_post_create(), sepgsql_proc_setattr(), sepgsql_relation_post_create(), sepgsql_relation_setattr(), sepgsql_relation_setattr_extra(), sepgsql_schema_post_create(), sequenceIsOwned(), SetSecurityLabel(), SetSharedSecurityLabel(), shdepChangeDep(), shdepDropDependency(), shdepDropOwned(), shdepReassignOwned(), systable_inplace_update_begin(), systable_inplace_update_cancel(), systable_inplace_update_finish(), toastrel_valueid_exists(), TriggerSetParentTrigger(), typeInheritsFrom(), vac_update_datfrozenxid(), and validatePartitionedIndex().

systable_endscan_ordered()

void systable_endscan_ordered

(

SysScanDesc

sysscan

)

Definition at line 757 of file genam.c.

{
    if (sysscan->slot)
    {
        ExecDropSingleTupleTableSlot(sysscan->slot);
        sysscan->slot = NULL;
    }
 
    Assert(sysscan->irel);
    index_endscan(sysscan->iscan);
    if (sysscan->snapshot)
        UnregisterSnapshot(sysscan->snapshot);
 
    /*
     * Reset the bsysscan flag at the end of the systable scan.  See detailed
     * comments in xact.c where these variables are declared.
     */
    if (TransactionIdIsValid(CheckXidAlive))
        bsysscan = false;
 
    pfree(sysscan);
}

References Assert(), bsysscan, CheckXidAlive, ExecDropSingleTupleTableSlot(), index_endscan(), SysScanDescData::irel, SysScanDescData::iscan, pfree(), SysScanDescData::slot, SysScanDescData::snapshot, TransactionIdIsValid, and UnregisterSnapshot().

Referenced by BuildEventTriggerCache(), check_toasted_attribute(), enum_endpoint(), enum_range_internal(), heap_fetch_toast_slice(), inv_getsize(), inv_read(), inv_truncate(), inv_write(), lookup_ts_config_cache(), and toast_delete_datum().

systable_getnext()

HeapTuple systable_getnext

(

SysScanDesc

sysscan

)

Definition at line 514 of file genam.c.

{
    HeapTuple   htup = NULL;
 
    if (sysscan->irel)
    {
        if (index_getnext_slot(sysscan->iscan, ForwardScanDirection, sysscan->slot))
        {
            bool        shouldFree;
 
            htup = ExecFetchSlotHeapTuple(sysscan->slot, false, &shouldFree);
            Assert(!shouldFree);
 
            /*
             * We currently don't need to support lossy index operators for
             * any system catalog scan.  It could be done here, using the scan
             * keys to drive the operator calls, if we arranged to save the
             * heap attnums during systable_beginscan(); this is practical
             * because we still wouldn't need to support indexes on
             * expressions.
             */
            if (sysscan->iscan->xs_recheck)
                elog(ERROR, "system catalog scans with lossy index conditions are not implemented");
        }
    }
    else
    {
        if (table_scan_getnextslot(sysscan->scan, ForwardScanDirection, sysscan->slot))
        {
            bool        shouldFree;
 
            htup = ExecFetchSlotHeapTuple(sysscan->slot, false, &shouldFree);
            Assert(!shouldFree);
        }
    }
 
    /*
     * Handle the concurrent abort while fetching the catalog tuple during
     * logical streaming of a transaction.
     */
    HandleConcurrentAbort();
 
    return htup;
}

References Assert(), elog, ERROR, ExecFetchSlotHeapTuple(), ForwardScanDirection, HandleConcurrentAbort(), index_getnext_slot(), SysScanDescData::irel, SysScanDescData::iscan, SysScanDescData::scan, SysScanDescData::slot, table_scan_getnextslot(), and IndexScanDescData::xs_recheck.

Referenced by AfterTriggerSetState(), AlterConstraintNamespaces(), AlterConstrDeferrabilityRecurse(), AlterConstrEnforceabilityRecurse(), AlterConstrTriggerDeferrability(), AlterDatabase(), AlterDatabaseOwner(), AlterDatabaseRefreshColl(), AlterDomainDropConstraint(), AlterDomainValidateConstraint(), AlterExtensionNamespace(), AlterPolicy(), AlterSeqNamespaces(), AlterSetting(), AlterTypeRecurse(), ApplyExtensionUpdates(), ApplySetting(), ATExecAddOf(), ATExecAlterColumnType(), ATExecAlterConstraint(), ATExecAttachPartition(), ATExecDropConstraint(), ATExecValidateConstraint(), ATPrepChangePersistence(), AttrDefaultFetch(), change_owner_fix_column_acls(), change_owner_recurse_to_sequences(), changeDependenciesOf(), changeDependenciesOn(), changeDependencyFor(), CheckNNConstraintFetch(), checkSharedDependencies(), ChooseConstraintName(), CloneFkReferenced(), CloneRowTriggersToPartition(), ConstraintNameExists(), ConstraintNameIsUsed(), CopyStatistics(), copyTemplateDependencies(), CountDBSubscriptions(), CreateComments(), CreateInheritance(), CreatePolicy(), CreateSharedComments(), CreateTriggerFiringOn(), DefineOpClass(), DefineTSConfiguration(), DeleteAttributeTuples(), DeleteComments(), deleteDependencyRecordsFor(), deleteDependencyRecordsForClass(), deleteDependencyRecordsForSpecific(), DeleteInheritsTuple(), DeleteInitPrivs(), deleteOneObject(), DeleteSecurityLabel(), DeleteSharedComments(), DeleteSharedSecurityLabel(), DeleteSystemAttributeTuples(), drop_parent_dependency(), DropClonedTriggersFromPartition(), DropConfigurationMapping(), dropconstraint_internal(), dropDatabaseDependencies(), DropForeignKeyConstraintTriggers(), DropObjectById(), DropRole(), EnableDisableTrigger(), EnumValuesDelete(), exec_object_restorecon(), ExecAlterExtensionStmt(), ExecGrant_Largeobject(), extension_config_remove(), fetch_statentries_for_relation(), find_composite_type_dependencies(), find_inheritance_children_extended(), findDependentObjects(), findDomainNotNullConstraint(), findNotNullConstraintAttnum(), get_catalog_object_by_oid_extended(), get_database_oid(), get_db_info(), get_domain_constraint_oid(), get_index_constraint(), get_index_ref_constraints(), get_partition_parent_worker(), get_pkey_attnames(), get_primary_key_attnos(), get_relation_constraint_attnos(), get_relation_constraint_oid(), get_relation_idx_constraint_oid(), get_relation_policy_oid(), get_rels_with_domain(), get_trigger_oid(), GetAllTablesPublications(), GetAttrDefaultColumnAddress(), GetAttrDefaultOid(), getAutoExtensionsOfObject(), GetComment(), GetDatabaseTuple(), GetDatabaseTupleByOid(), GetDefaultOpClass(), getExtensionOfObject(), GetForeignKeyActionTriggers(), GetForeignKeyCheckTriggers(), GetNewOidWithIndex(), getObjectDescription(), getObjectIdentityParts(), getOwnedSequences_internal(), GetParentedForeignKeyRefs(), GetPublicationRelations(), GetPublicationSchemas(), GetSecurityLabel(), GetSharedSecurityLabel(), GetSubscriptionRelations(), has_superclass(), HasSubscriptionRelations(), heap_truncate_find_FKs(), index_concurrently_swap(), IndexSetParentIndex(), is_schema_publication(), LargeObjectDrop(), LargeObjectExistsWithSnapshot(), load_domaintype_info(), load_enum_cache_data(), LookupOpclassInfo(), makeConfigurationDependencies(), MakeConfigurationMapping(), MarkInheritDetached(), MergeConstraintsIntoExisting(), MergeWithExistingConstraint(), movedb(), object_ownercheck(), PartitionHasPendingDetach(), pg_extension_config_dump(), pg_get_constraintdef_worker(), pg_get_serial_sequence(), pg_get_triggerdef_worker(), pg_largeobject_aclmask_snapshot(), QueueFKConstraintValidation(), RangeDelete(), recordExtensionInitPrivWorker(), recordExtObjInitPriv(), relation_has_policies(), RelationBuildPartitionDesc(), RelationBuildRowSecurity(), RelationBuildRuleLock(), RelationBuildTriggers(), RelationBuildTupleDesc(), RelationGetExclusionInfo(), RelationGetFKeyList(), RelationGetIndexList(), RelationGetNotNullConstraints(), RelationGetStatExtList(), RelationRemoveInheritance(), RelidByRelfilenumber(), RememberAllDependentForRebuilding(), RemoveAttrDefault(), RemoveAttrDefaultById(), RemoveExtensionById(), RemoveInheritance(), RemoveInheritedConstraint(), RemovePolicyById(), RemoveRewriteRuleById(), RemoveRoleFromInitPriv(), RemoveRoleFromObjectACL(), RemoveRoleFromObjectPolicy(), RemoveStatistics(), RemoveTriggerById(), RemoveTSConfigurationById(), rename_policy(), renametrig(), renametrig_internal(), renametrig_partition(), ReplaceRoleInInitPriv(), replorigin_create(), ScanPgRelation(), SearchCatCacheList(), SearchCatCacheMiss(), sepgsql_attribute_post_create(), sepgsql_database_post_create(), sepgsql_proc_post_create(), sepgsql_proc_setattr(), sepgsql_relation_post_create(), sepgsql_relation_setattr(), sepgsql_relation_setattr_extra(), sepgsql_schema_post_create(), sequenceIsOwned(), SetSecurityLabel(), SetSharedSecurityLabel(), shdepChangeDep(), shdepDropDependency(), shdepDropOwned(), shdepReassignOwned(), systable_inplace_update_begin(), toastrel_valueid_exists(), TriggerSetParentTrigger(), typeInheritsFrom(), vac_update_datfrozenxid(), and validatePartitionedIndex().

systable_getnext_ordered()

HeapTuple systable_getnext_ordered	(	SysScanDesc	sysscan,
		ScanDirection	direction
	)

Definition at line 732 of file genam.c.

{
    HeapTuple   htup = NULL;
 
    Assert(sysscan->irel);
    if (index_getnext_slot(sysscan->iscan, direction, sysscan->slot))
        htup = ExecFetchSlotHeapTuple(sysscan->slot, false, NULL);
 
    /* See notes in systable_getnext */
    if (htup && sysscan->iscan->xs_recheck)
        elog(ERROR, "system catalog scans with lossy index conditions are not implemented");
 
    /*
     * Handle the concurrent abort while fetching the catalog tuple during
     * logical streaming of a transaction.
     */
    HandleConcurrentAbort();
 
    return htup;
}

References Assert(), elog, ERROR, ExecFetchSlotHeapTuple(), HandleConcurrentAbort(), index_getnext_slot(), SysScanDescData::irel, SysScanDescData::iscan, SysScanDescData::slot, and IndexScanDescData::xs_recheck.

Referenced by BuildEventTriggerCache(), check_toasted_attribute(), enum_endpoint(), enum_range_internal(), heap_fetch_toast_slice(), inv_getsize(), inv_read(), inv_truncate(), inv_write(), lookup_ts_config_cache(), and toast_delete_datum().

systable_inplace_update_begin()

void systable_inplace_update_begin	(	Relation	relation,
		Oid	indexId,
		bool	indexOK,
		Snapshot	snapshot,
		int	nkeys,
		const ScanKeyData *	key,
		HeapTuple *	oldtupcopy,
		void **	state
	)

Definition at line 807 of file genam.c.

{
    int         retries = 0;
    SysScanDesc scan;
    HeapTuple   oldtup;
    BufferHeapTupleTableSlot *bslot;
 
    /*
     * For now, we don't allow parallel updates.  Unlike a regular update,
     * this should never create a combo CID, so it might be possible to relax
     * this restriction, but not without more thought and testing.  It's not
     * clear that it would be useful, anyway.
     */
    if (IsInParallelMode())
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_TRANSACTION_STATE),
                 errmsg("cannot update tuples during a parallel operation")));
 
    /*
     * Accept a snapshot argument, for symmetry, but this function advances
     * its snapshot as needed to reach the tail of the updated tuple chain.
     */
    Assert(snapshot == NULL);
 
    Assert(IsInplaceUpdateRelation(relation) || !IsSystemRelation(relation));
 
    /* Loop for an exclusive-locked buffer of a non-updated tuple. */
    do
    {
        TupleTableSlot *slot;
 
        CHECK_FOR_INTERRUPTS();
 
        /*
         * Processes issuing heap_update (e.g. GRANT) at maximum speed could
         * drive us to this error.  A hostile table owner has stronger ways to
         * damage their own table, so that's minor.
         */
        if (retries++ > 10000)
            elog(ERROR, "giving up after too many tries to overwrite row");
 
        INJECTION_POINT("inplace-before-pin");
        scan = systable_beginscan(relation, indexId, indexOK, snapshot,
                                  nkeys, unconstify(ScanKeyData *, key));
        oldtup = systable_getnext(scan);
        if (!HeapTupleIsValid(oldtup))
        {
            systable_endscan(scan);
            *oldtupcopy = NULL;
            return;
        }
 
        slot = scan->slot;
        Assert(TTS_IS_BUFFERTUPLE(slot));
        bslot = (BufferHeapTupleTableSlot *) slot;
    } while (!heap_inplace_lock(scan->heap_rel,
                                bslot->base.tuple, bslot->buffer,
                                (void (*) (void *)) systable_endscan, scan));
 
    *oldtupcopy = heap_copytuple(oldtup);
    *state = scan;
}

References Assert(), BufferHeapTupleTableSlot::buffer, CHECK_FOR_INTERRUPTS, elog, ereport, errcode(), errmsg(), ERROR, heap_copytuple(), heap_inplace_lock(), SysScanDescData::heap_rel, HeapTupleIsValid, INJECTION_POINT, IsInParallelMode(), IsInplaceUpdateRelation(), IsSystemRelation(), sort-test::key, SysScanDescData::slot, systable_beginscan(), systable_endscan(), systable_getnext(), TTS_IS_BUFFERTUPLE, and unconstify.

Referenced by create_toast_table(), dropdb(), EventTriggerOnLogin(), index_update_stats(), vac_update_datfrozenxid(), and vac_update_relstats().

systable_inplace_update_cancel()

void systable_inplace_update_cancel

(

void *

state

)

Definition at line 902 of file genam.c.

{
    SysScanDesc scan = (SysScanDesc) state;
    Relation    relation = scan->heap_rel;
    TupleTableSlot *slot = scan->slot;
    BufferHeapTupleTableSlot *bslot = (BufferHeapTupleTableSlot *) slot;
    HeapTuple   oldtup = bslot->base.tuple;
    Buffer      buffer = bslot->buffer;
 
    heap_inplace_unlock(relation, oldtup, buffer);
    systable_endscan(scan);
}

References BufferHeapTupleTableSlot::buffer, heap_inplace_unlock(), SysScanDescData::heap_rel, SysScanDescData::slot, and systable_endscan().

Referenced by EventTriggerOnLogin(), index_update_stats(), vac_update_datfrozenxid(), and vac_update_relstats().

systable_inplace_update_finish()

void systable_inplace_update_finish	(	void *	state,
		HeapTuple	tuple
	)

Definition at line 883 of file genam.c.

{
    SysScanDesc scan = (SysScanDesc) state;
    Relation    relation = scan->heap_rel;
    TupleTableSlot *slot = scan->slot;
    BufferHeapTupleTableSlot *bslot = (BufferHeapTupleTableSlot *) slot;
    HeapTuple   oldtup = bslot->base.tuple;
    Buffer      buffer = bslot->buffer;
 
    heap_inplace_update_and_unlock(relation, oldtup, tuple, buffer);
    systable_endscan(scan);
}

References BufferHeapTupleTableSlot::buffer, heap_inplace_update_and_unlock(), SysScanDescData::heap_rel, SysScanDescData::slot, and systable_endscan().

Referenced by create_toast_table(), dropdb(), EventTriggerOnLogin(), index_update_stats(), vac_update_datfrozenxid(), and vac_update_relstats().

systable_recheck_tuple()

bool systable_recheck_tuple	(	SysScanDesc	sysscan,
		HeapTuple	tup
	)

Definition at line 573 of file genam.c.

{
    Snapshot    freshsnap;
    bool        result;
 
    Assert(tup == ExecFetchSlotHeapTuple(sysscan->slot, false, NULL));
 
    freshsnap = GetCatalogSnapshot(RelationGetRelid(sysscan->heap_rel));
    freshsnap = RegisterSnapshot(freshsnap);
 
    result = table_tuple_satisfies_snapshot(sysscan->heap_rel,
                                            sysscan->slot,
                                            freshsnap);
    UnregisterSnapshot(freshsnap);
 
    /*
     * Handle the concurrent abort while fetching the catalog tuple during
     * logical streaming of a transaction.
     */
    HandleConcurrentAbort();
 
    return result;
}

References Assert(), ExecFetchSlotHeapTuple(), GetCatalogSnapshot(), HandleConcurrentAbort(), SysScanDescData::heap_rel, RegisterSnapshot(), RelationGetRelid, SysScanDescData::slot, table_tuple_satisfies_snapshot(), and UnregisterSnapshot().

Referenced by findDependentObjects(), and shdepDropOwned().