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 (void)
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(), fb(), Form_pg_index, 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 ( void  )

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, fb(), 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_array(TM_IndexDelete, nitems);
    delstate.status = palloc_array(TM_IndexStatus, nitems);
 
    /* 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, BufferGetBlockNumber(), BufferGetPage(), fb(), i, InvalidTransactionId, ItemIdIsDead, ItemPointerCopy(), nitems, PageGetItem(), PageGetItemId(), palloc_array, pfree(), IndexTupleData::t_tid, and table_index_delete_tuples().

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 fb(), 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 = palloc_object(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 = palloc_array(ScanKeyData, nkeys);
    else
        scan->keyData = NULL;
    if (norderbys > 0)
        scan->orderByData = palloc_array(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 fb(), 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_array, palloc_object, 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 = palloc_object(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 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;
 
    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;
    }
 
    return sysscan;
}

References AccessShareLock, bsysscan, CheckXidAlive, elog, ERROR, fb(), GetCatalogSnapshot(), i, IgnoreSystemIndexes, index_beginscan(), index_open(), index_rescan(), IndexRelationGetNumberOfAttributes, j, palloc_array, palloc_object, pfree(), RelationData::rd_index, RegisterSnapshot(), ReindexIsProcessingIndex(), RelationGetRelid, table_beginscan_strat(), table_slot_create(), and TransactionIdIsValid.

Referenced by AfterTriggerSetState(), AlterCheckConstrEnforceabilityRecurse(), AlterConstraintNamespaces(), AlterConstrDeferrabilityRecurse(), AlterConstrTriggerDeferrability(), AlterDatabase(), AlterDatabaseOwner(), AlterDatabaseRefreshColl(), AlterDomainDropConstraint(), AlterDomainValidateConstraint(), AlterExtensionNamespace(), AlterFKConstrEnforceabilityRecurse(), AlterPolicy(), AlterPropGraph(), 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(), check_element_label_properties(), check_element_properties(), CheckNNConstraintFetch(), checkSharedDependencies(), ChooseConstraintName(), ChooseRelationName(), 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(), EventTriggerSQLDropAddObject(), 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_element_label_property_names(), get_element_property_expr(), get_graph_label_ids(), get_graph_property_ids(), get_index_constraint(), get_index_ref_constraints(), get_label_element_label_ids(), get_labels_for_expr(), get_partition_parent_worker(), get_path_elements_for_path_factor(), get_pg_statistic_ext(), get_pkey_attnames(), get_primary_key_attnos(), get_publication_relations(), 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(), getExtensionType(), GetForeignKeyActionTriggers(), GetForeignKeyCheckTriggers(), GetNewOidWithIndex(), getObjectDescription(), getObjectIdentityParts(), getOwnedSequences_internal(), GetParentedForeignKeyRefs(), GetPublicationSchemas(), GetSecurityLabel(), GetSharedSecurityLabel(), GetSubscriptionRelations(), has_superclass(), HasSubscriptionTables(), heap_truncate_find_FKs(), index_concurrently_swap(), IndexSetParentIndex(), insert_property_records(), is_property_associated_with_label(), is_schema_publication(), LargeObjectDrop(), LargeObjectExistsWithSnapshot(), load_domaintype_info(), load_enum_cache_data(), LogicalRepSyncSequences(), LookupOpclassInfo(), make_propgraphdef_elements(), make_propgraphdef_labels(), make_propgraphdef_properties(), 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 = palloc_object(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");
    }
 
    /*
     * 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;
 
    sysscan->iscan = index_beginscan(heapRelation, indexRelation,
                                     snapshot, NULL, nkeys, 0);
    index_rescan(sysscan->iscan, idxkey, nkeys, NULL, 0);
    sysscan->scan = NULL;
 
    pfree(idxkey);
 
    return sysscan;
}

References bsysscan, CheckXidAlive, elog, ereport, errcode(), errmsg, ERROR, fb(), GetCatalogSnapshot(), i, IgnoreSystemIndexes, index_beginscan(), index_rescan(), IndexRelationGetNumberOfAttributes, j, palloc_array, palloc_object, pfree(), RelationData::rd_index, RegisterSnapshot(), ReindexIsProcessingIndex(), RelationGetRelationName, RelationGetRelid, 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(), fb(), index_close(), index_endscan(), pfree(), table_endscan(), TransactionIdIsValid, and UnregisterSnapshot().

Referenced by AfterTriggerSetState(), AlterCheckConstrEnforceabilityRecurse(), AlterConstraintNamespaces(), AlterConstrDeferrabilityRecurse(), AlterConstrTriggerDeferrability(), AlterDatabase(), AlterDatabaseOwner(), AlterDatabaseRefreshColl(), AlterDomainDropConstraint(), AlterDomainValidateConstraint(), AlterExtensionNamespace(), AlterFKConstrEnforceabilityRecurse(), AlterPolicy(), AlterPropGraph(), 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(), check_element_label_properties(), check_element_properties(), CheckNNConstraintFetch(), checkSharedDependencies(), ChooseConstraintName(), ChooseRelationName(), 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(), EventTriggerSQLDropAddObject(), 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_element_label_property_names(), get_element_property_expr(), get_graph_label_ids(), get_graph_property_ids(), get_index_constraint(), get_index_ref_constraints(), get_label_element_label_ids(), get_labels_for_expr(), get_partition_parent_worker(), get_path_elements_for_path_factor(), get_pg_statistic_ext(), get_pkey_attnames(), get_primary_key_attnos(), get_publication_relations(), 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(), getExtensionType(), GetForeignKeyActionTriggers(), GetForeignKeyCheckTriggers(), GetNewOidWithIndex(), getObjectDescription(), getObjectIdentityParts(), getOwnedSequences_internal(), GetParentedForeignKeyRefs(), GetPublicationSchemas(), GetSecurityLabel(), GetSharedSecurityLabel(), GetSubscriptionRelations(), has_superclass(), HasSubscriptionTables(), heap_truncate_find_FKs(), index_concurrently_swap(), IndexSetParentIndex(), insert_property_records(), is_property_associated_with_label(), is_schema_publication(), LargeObjectDrop(), LargeObjectExistsWithSnapshot(), load_domaintype_info(), load_enum_cache_data(), LogicalRepSyncSequences(), LookupOpclassInfo(), make_propgraphdef_elements(), make_propgraphdef_labels(), make_propgraphdef_properties(), 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(), fb(), index_endscan(), pfree(), 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(), fb(), ForwardScanDirection, HandleConcurrentAbort(), index_getnext_slot(), and table_scan_getnextslot().

Referenced by AfterTriggerSetState(), AlterCheckConstrEnforceabilityRecurse(), AlterConstraintNamespaces(), AlterConstrDeferrabilityRecurse(), AlterConstrTriggerDeferrability(), AlterDatabase(), AlterDatabaseOwner(), AlterDatabaseRefreshColl(), AlterDomainDropConstraint(), AlterDomainValidateConstraint(), AlterExtensionNamespace(), AlterFKConstrEnforceabilityRecurse(), AlterPolicy(), AlterPropGraph(), 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(), check_element_label_properties(), check_element_properties(), CheckNNConstraintFetch(), checkSharedDependencies(), ChooseConstraintName(), ChooseRelationName(), 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(), EventTriggerSQLDropAddObject(), 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_element_label_property_names(), get_element_property_expr(), get_graph_label_ids(), get_graph_property_ids(), get_index_constraint(), get_index_ref_constraints(), get_label_element_label_ids(), get_labels_for_expr(), get_partition_parent_worker(), get_path_elements_for_path_factor(), get_pg_statistic_ext(), get_pkey_attnames(), get_primary_key_attnos(), get_publication_relations(), 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(), getExtensionType(), GetForeignKeyActionTriggers(), GetForeignKeyCheckTriggers(), GetNewOidWithIndex(), getObjectDescription(), getObjectIdentityParts(), getOwnedSequences_internal(), GetParentedForeignKeyRefs(), GetPublicationSchemas(), GetSecurityLabel(), GetSharedSecurityLabel(), GetSubscriptionRelations(), has_superclass(), HasSubscriptionTables(), heap_truncate_find_FKs(), index_concurrently_swap(), IndexSetParentIndex(), insert_property_records(), is_property_associated_with_label(), is_schema_publication(), LargeObjectDrop(), LargeObjectExistsWithSnapshot(), load_domaintype_info(), load_enum_cache_data(), LogicalRepSyncSequences(), LookupOpclassInfo(), make_propgraphdef_elements(), make_propgraphdef_labels(), make_propgraphdef_properties(), 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(), fb(), HandleConcurrentAbort(), and index_getnext_slot().

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 808 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", NULL);
        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, CHECK_FOR_INTERRUPTS, elog, ereport, errcode(), errmsg, ERROR, fb(), heap_copytuple(), heap_inplace_lock(), SysScanDescData::heap_rel, HeapTupleIsValid, INJECTION_POINT, IsInParallelMode(), IsInplaceUpdateRelation(), IsSystemRelation(), 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 903 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 fb(), 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 884 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 fb(), 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(), fb(), GetCatalogSnapshot(), HandleConcurrentAbort(), RegisterSnapshot(), RelationGetRelid, table_tuple_satisfies_snapshot(), and UnregisterSnapshot().

Referenced by findDependentObjects(), and shdepDropOwned().