#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/builtins.h"
#include "utils/lsyscache.h"
#include "utils/rel.h"
#include "utils/rls.h"
#include "utils/ruleutils.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"

Include dependency graph for genam.c:

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

void	IndexScanEnd (IndexScanDesc scan)

char *	BuildIndexValueDescription (Relation indexRelation, Datum values, 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)

Function Documentation

◆ BuildIndexValueDescription()

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

Definition at line 177 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(), check_exclusion_or_unique_constraint(), and comparetup_index_btree_tiebreak().

◆ HandleConcurrentAbort()

static void HandleConcurrentAbort ( )

inlinestatic

Definition at line 483 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 294 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 81 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->xs_itup = NULL;
     scan->xs_itupdesc = NULL;
     scan->xs_hitup = NULL;
     scan->xs_hitupdesc = NULL;
  
     return scan;
 }

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 387 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;
  
         /* Change attribute numbers to be index column numbers. */
         for (i = 0; i < nkeys; i++)
         {
             int         j;
  
             for (j = 0; j < IndexRelationGetNumberOfAttributes(irel); j++)
             {
                 if (key[i].sk_attno == irel->rd_index->indkey.values[j])
                 {
                     key[i].sk_attno = j + 1;
                     break;
                 }
             }
             if (j == IndexRelationGetNumberOfAttributes(irel))
                 elog(ERROR, "column is not in index");
         }
  
         sysscan->iscan = index_beginscan(heapRelation, irel,
                                          snapshot, nkeys, 0);
         index_rescan(sysscan->iscan, key, nkeys, NULL, 0);
         sysscan->scan = NULL;
     }
     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(), RelationData::rd_index, RegisterSnapshot(), ReindexIsProcessingIndex(), RelationGetRelid, SysScanDescData::scan, SysScanDescData::slot, SysScanDescData::snapshot, table_beginscan_strat(), table_slot_create(), and TransactionIdIsValid.

Referenced by AfterTriggerSetState(), AlterConstraintNamespaces(), AlterDatabase(), AlterDatabaseOwner(), AlterDatabaseRefreshColl(), AlterDomainDropConstraint(), AlterDomainValidateConstraint(), AlterExtensionNamespace(), AlterPolicy(), AlterSeqNamespaces(), AlterSetting(), AlterTypeRecurse(), ApplyExtensionUpdates(), ApplySetting(), ATExecAddOf(), ATExecAlterColumnType(), ATExecAlterConstraint(), ATExecAlterConstrRecurse(), ATExecAttachPartition(), ATExecDropConstraint(), ATExecSetNotNull(), ATExecValidateConstraint(), ATPrepChangePersistence(), AttrDefaultFetch(), change_owner_fix_column_acls(), change_owner_recurse_to_sequences(), changeDependenciesOf(), changeDependenciesOn(), changeDependencyFor(), CheckConstraintFetch(), 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(), 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(), findNotNullConstraintAttnum(), get_catalog_object_by_oid(), get_database_oid(), get_db_info(), get_domain_constraint_oid(), get_extension_name(), get_extension_oid(), get_extension_schema(), 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(), LargeObjectExists(), load_domaintype_info(), load_enum_cache_data(), LookupOpclassInfo(), makeConfigurationDependencies(), MakeConfigurationMapping(), MarkInheritDetached(), MergeConstraintsIntoExisting(), MergeWithExistingConstraint(), movedb(), myLargeObjectExists(), object_ownercheck(), PartitionHasPendingDetach(), pg_extension_config_dump(), pg_get_constraintdef_worker(), pg_get_serial_sequence(), pg_get_triggerdef_worker(), pg_largeobject_aclmask_snapshot(), RangeDelete(), recordExtensionInitPrivWorker(), recordExtObjInitPriv(), relation_has_policies(), RelationBuildPartitionDesc(), RelationBuildRowSecurity(), RelationBuildRuleLock(), RelationBuildTriggers(), RelationBuildTupleDesc(), RelationGetExclusionInfo(), RelationGetFKeyList(), RelationGetIndexList(), RelationGetNotNullConstraints(), RelationGetStatExtList(), RelationRemoveInheritance(), RelidByRelfilenumber(), RemoveAttrDefault(), RemoveAttrDefaultById(), RemoveExtensionById(), RemoveInheritance(), RemovePolicyById(), RemoveRewriteRuleById(), RemoveRoleFromObjectACL(), RemoveRoleFromObjectPolicy(), RemoveStatistics(), RemoveTriggerById(), RemoveTSConfigurationById(), rename_policy(), renametrig(), renametrig_internal(), renametrig_partition(), 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(), toastrel_valueid_exists(), TriggerSetParentTrigger(), tryAttachPartitionForeignKey(), 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 646 of file genam.c.

 {
     SysScanDesc sysscan;
     int         i;
  
     /* REINDEX can probably be a hard error here ... */
     if (ReindexIsProcessingIndex(RelationGetRelid(indexRelation)))
         elog(ERROR, "cannot do ordered scan on index \"%s\", because 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;
     }
  
     /* Change attribute numbers to be index column numbers. */
     for (i = 0; i < nkeys; i++)
     {
         int         j;
  
         for (j = 0; j < IndexRelationGetNumberOfAttributes(indexRelation); j++)
         {
             if (key[i].sk_attno == indexRelation->rd_index->indkey.values[j])
             {
                 key[i].sk_attno = j + 1;
                 break;
             }
         }
         if (j == IndexRelationGetNumberOfAttributes(indexRelation))
             elog(ERROR, "column is not in index");
     }
  
     sysscan->iscan = index_beginscan(heapRelation, indexRelation,
                                      snapshot, nkeys, 0);
     index_rescan(sysscan->iscan, key, nkeys, NULL, 0);
     sysscan->scan = NULL;
  
     return sysscan;
 }

References elog(), ERROR, GetCatalogSnapshot(), SysScanDescData::heap_rel, i, IgnoreSystemIndexes, index_beginscan(), index_rescan(), IndexRelationGetNumberOfAttributes, SysScanDescData::irel, SysScanDescData::iscan, j, sort-test::key, palloc(), RelationData::rd_index, RegisterSnapshot(), ReindexIsProcessingIndex(), RelationGetRelationName, RelationGetRelid, SysScanDescData::scan, SysScanDescData::slot, SysScanDescData::snapshot, table_slot_create(), 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 599 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(), AlterDatabase(), AlterDatabaseOwner(), AlterDatabaseRefreshColl(), AlterDomainDropConstraint(), AlterDomainValidateConstraint(), AlterExtensionNamespace(), AlterPolicy(), AlterSeqNamespaces(), AlterSetting(), AlterTypeRecurse(), ApplyExtensionUpdates(), ApplySetting(), ATExecAddOf(), ATExecAlterColumnType(), ATExecAlterConstraint(), ATExecAlterConstrRecurse(), ATExecAttachPartition(), ATExecDropConstraint(), ATExecSetNotNull(), ATExecValidateConstraint(), ATPrepChangePersistence(), AttrDefaultFetch(), change_owner_fix_column_acls(), change_owner_recurse_to_sequences(), changeDependenciesOf(), changeDependenciesOn(), changeDependencyFor(), CheckConstraintFetch(), 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(), 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(), findNotNullConstraintAttnum(), get_catalog_object_by_oid(), get_database_oid(), get_db_info(), get_domain_constraint_oid(), get_extension_name(), get_extension_oid(), get_extension_schema(), 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(), LargeObjectExists(), load_domaintype_info(), load_enum_cache_data(), LookupOpclassInfo(), makeConfigurationDependencies(), MakeConfigurationMapping(), MarkInheritDetached(), MergeConstraintsIntoExisting(), MergeWithExistingConstraint(), movedb(), myLargeObjectExists(), object_ownercheck(), PartitionHasPendingDetach(), pg_extension_config_dump(), pg_get_constraintdef_worker(), pg_get_serial_sequence(), pg_get_triggerdef_worker(), pg_largeobject_aclmask_snapshot(), RangeDelete(), recordExtensionInitPrivWorker(), recordExtObjInitPriv(), relation_has_policies(), RelationBuildPartitionDesc(), RelationBuildRowSecurity(), RelationBuildRuleLock(), RelationBuildTriggers(), RelationBuildTupleDesc(), RelationGetExclusionInfo(), RelationGetFKeyList(), RelationGetIndexList(), RelationGetNotNullConstraints(), RelationGetStatExtList(), RelationRemoveInheritance(), RelidByRelfilenumber(), RemoveAttrDefault(), RemoveAttrDefaultById(), RemoveExtensionById(), RemoveInheritance(), RemovePolicyById(), RemoveRewriteRuleById(), RemoveRoleFromObjectACL(), RemoveRoleFromObjectPolicy(), RemoveStatistics(), RemoveTriggerById(), RemoveTSConfigurationById(), rename_policy(), renametrig(), renametrig_internal(), renametrig_partition(), 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(), toastrel_valueid_exists(), TriggerSetParentTrigger(), tryAttachPartitionForeignKey(), typeInheritsFrom(), vac_update_datfrozenxid(), and validatePartitionedIndex().

◆ systable_endscan_ordered()

void systable_endscan_ordered ( SysScanDesc sysscan )

Definition at line 736 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);
     pfree(sysscan);
 }

References Assert(), ExecDropSingleTupleTableSlot(), index_endscan(), SysScanDescData::irel, SysScanDescData::iscan, pfree(), SysScanDescData::slot, SysScanDescData::snapshot, 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 506 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(), AlterDatabase(), AlterDatabaseOwner(), AlterDatabaseRefreshColl(), AlterDomainDropConstraint(), AlterDomainValidateConstraint(), AlterExtensionNamespace(), AlterPolicy(), AlterSeqNamespaces(), AlterSetting(), AlterTypeRecurse(), ApplyExtensionUpdates(), ApplySetting(), ATExecAddOf(), ATExecAlterColumnType(), ATExecAlterConstraint(), ATExecAlterConstrRecurse(), ATExecAttachPartition(), ATExecDropConstraint(), ATExecSetNotNull(), ATExecValidateConstraint(), ATPrepChangePersistence(), AttrDefaultFetch(), change_owner_fix_column_acls(), change_owner_recurse_to_sequences(), changeDependenciesOf(), changeDependenciesOn(), changeDependencyFor(), CheckConstraintFetch(), 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(), 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(), findNotNullConstraintAttnum(), get_catalog_object_by_oid(), get_database_oid(), get_db_info(), get_domain_constraint_oid(), get_extension_name(), get_extension_oid(), get_extension_schema(), 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(), LargeObjectExists(), load_domaintype_info(), load_enum_cache_data(), LookupOpclassInfo(), makeConfigurationDependencies(), MakeConfigurationMapping(), MarkInheritDetached(), MergeConstraintsIntoExisting(), MergeWithExistingConstraint(), movedb(), myLargeObjectExists(), object_ownercheck(), PartitionHasPendingDetach(), pg_extension_config_dump(), pg_get_constraintdef_worker(), pg_get_serial_sequence(), pg_get_triggerdef_worker(), pg_largeobject_aclmask_snapshot(), RangeDelete(), recordExtensionInitPrivWorker(), recordExtObjInitPriv(), relation_has_policies(), RelationBuildPartitionDesc(), RelationBuildRowSecurity(), RelationBuildRuleLock(), RelationBuildTriggers(), RelationBuildTupleDesc(), RelationGetExclusionInfo(), RelationGetFKeyList(), RelationGetIndexList(), RelationGetNotNullConstraints(), RelationGetStatExtList(), RelationRemoveInheritance(), RelidByRelfilenumber(), RemoveAttrDefault(), RemoveAttrDefaultById(), RemoveExtensionById(), RemoveInheritance(), RemovePolicyById(), RemoveRewriteRuleById(), RemoveRoleFromObjectACL(), RemoveRoleFromObjectPolicy(), RemoveStatistics(), RemoveTriggerById(), RemoveTSConfigurationById(), rename_policy(), renametrig(), renametrig_internal(), renametrig_partition(), 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(), toastrel_valueid_exists(), TriggerSetParentTrigger(), tryAttachPartitionForeignKey(), typeInheritsFrom(), vac_update_datfrozenxid(), and validatePartitionedIndex().

◆ systable_getnext_ordered()

HeapTuple systable_getnext_ordered	(	SysScanDesc	sysscan,
		ScanDirection	direction
	)

Definition at line 711 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_recheck_tuple()

bool systable_recheck_tuple	(	SysScanDesc	sysscan,
		HeapTuple	tup
	)

Definition at line 565 of file genam.c.

 {
     Snapshot    freshsnap;
     bool        result;
  
     Assert(tup == ExecFetchSlotHeapTuple(sysscan->slot, false, NULL));
  
     /*
      * Trust that table_tuple_satisfies_snapshot() and its subsidiaries
      * (commonly LockBuffer() and HeapTupleSatisfiesMVCC()) do not themselves
      * acquire snapshots, so we need not register the snapshot.  Those
      * facilities are too low-level to have any business scanning tables.
      */
     freshsnap = GetCatalogSnapshot(RelationGetRelid(sysscan->heap_rel));
  
     result = table_tuple_satisfies_snapshot(sysscan->heap_rel,
                                             sysscan->slot,
                                             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, RelationGetRelid, SysScanDescData::slot, and table_tuple_satisfies_snapshot().

Referenced by findDependentObjects(), and shdepDropOwned().

Functions

Function Documentation

◆ BuildIndexValueDescription()

◆ HandleConcurrentAbort()

◆ index_compute_xid_horizon_for_tuples()

◆ IndexScanEnd()

◆ RelationGetIndexScan()

◆ systable_beginscan()

◆ systable_beginscan_ordered()

◆ systable_endscan()

◆ systable_endscan_ordered()

◆ systable_getnext()

◆ systable_getnext_ordered()

◆ systable_recheck_tuple()