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Diffstat (limited to 'src/backend/catalog/toasting.c')
| -rw-r--r-- | src/backend/catalog/toasting.c | 415 |
1 files changed, 415 insertions, 0 deletions
diff --git a/src/backend/catalog/toasting.c b/src/backend/catalog/toasting.c new file mode 100644 index 0000000..9bc1072 --- /dev/null +++ b/src/backend/catalog/toasting.c @@ -0,0 +1,415 @@ +/*------------------------------------------------------------------------- + * + * toasting.c + * This file contains routines to support creation of toast tables + * + * + * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * IDENTIFICATION + * src/backend/catalog/toasting.c + * + *------------------------------------------------------------------------- + */ +#include "postgres.h" + +#include "access/heapam.h" +#include "access/toast_compression.h" +#include "access/xact.h" +#include "catalog/binary_upgrade.h" +#include "catalog/catalog.h" +#include "catalog/dependency.h" +#include "catalog/heap.h" +#include "catalog/index.h" +#include "catalog/namespace.h" +#include "catalog/pg_am.h" +#include "catalog/pg_namespace.h" +#include "catalog/pg_opclass.h" +#include "catalog/pg_type.h" +#include "catalog/toasting.h" +#include "miscadmin.h" +#include "nodes/makefuncs.h" +#include "storage/lock.h" +#include "utils/builtins.h" +#include "utils/rel.h" +#include "utils/syscache.h" + +static void CheckAndCreateToastTable(Oid relOid, Datum reloptions, + LOCKMODE lockmode, bool check, + Oid OIDOldToast); +static bool create_toast_table(Relation rel, Oid toastOid, Oid toastIndexOid, + Datum reloptions, LOCKMODE lockmode, bool check, + Oid OIDOldToast); +static bool needs_toast_table(Relation rel); + + +/* + * CreateToastTable variants + * If the table needs a toast table, and doesn't already have one, + * then create a toast table for it. + * + * reloptions for the toast table can be passed, too. Pass (Datum) 0 + * for default reloptions. + * + * We expect the caller to have verified that the relation is a table and have + * already done any necessary permission checks. Callers expect this function + * to end with CommandCounterIncrement if it makes any changes. + */ +void +AlterTableCreateToastTable(Oid relOid, Datum reloptions, LOCKMODE lockmode) +{ + CheckAndCreateToastTable(relOid, reloptions, lockmode, true, InvalidOid); +} + +void +NewHeapCreateToastTable(Oid relOid, Datum reloptions, LOCKMODE lockmode, + Oid OIDOldToast) +{ + CheckAndCreateToastTable(relOid, reloptions, lockmode, false, OIDOldToast); +} + +void +NewRelationCreateToastTable(Oid relOid, Datum reloptions) +{ + CheckAndCreateToastTable(relOid, reloptions, AccessExclusiveLock, false, + InvalidOid); +} + +static void +CheckAndCreateToastTable(Oid relOid, Datum reloptions, LOCKMODE lockmode, + bool check, Oid OIDOldToast) +{ + Relation rel; + + rel = table_open(relOid, lockmode); + + /* create_toast_table does all the work */ + (void) create_toast_table(rel, InvalidOid, InvalidOid, reloptions, lockmode, + check, OIDOldToast); + + table_close(rel, NoLock); +} + +/* + * Create a toast table during bootstrap + * + * Here we need to prespecify the OIDs of the toast table and its index + */ +void +BootstrapToastTable(char *relName, Oid toastOid, Oid toastIndexOid) +{ + Relation rel; + + rel = table_openrv(makeRangeVar(NULL, relName, -1), AccessExclusiveLock); + + if (rel->rd_rel->relkind != RELKIND_RELATION && + rel->rd_rel->relkind != RELKIND_MATVIEW) + elog(ERROR, "\"%s\" is not a table or materialized view", + relName); + + /* create_toast_table does all the work */ + if (!create_toast_table(rel, toastOid, toastIndexOid, (Datum) 0, + AccessExclusiveLock, false, InvalidOid)) + elog(ERROR, "\"%s\" does not require a toast table", + relName); + + table_close(rel, NoLock); +} + + +/* + * create_toast_table --- internal workhorse + * + * rel is already opened and locked + * toastOid and toastIndexOid are normally InvalidOid, but during + * bootstrap they can be nonzero to specify hand-assigned OIDs + */ +static bool +create_toast_table(Relation rel, Oid toastOid, Oid toastIndexOid, + Datum reloptions, LOCKMODE lockmode, bool check, + Oid OIDOldToast) +{ + Oid relOid = RelationGetRelid(rel); + HeapTuple reltup; + TupleDesc tupdesc; + bool shared_relation; + bool mapped_relation; + Relation toast_rel; + Relation class_rel; + Oid toast_relid; + Oid namespaceid; + char toast_relname[NAMEDATALEN]; + char toast_idxname[NAMEDATALEN]; + IndexInfo *indexInfo; + Oid collationObjectId[2]; + Oid classObjectId[2]; + int16 coloptions[2]; + ObjectAddress baseobject, + toastobject; + + /* + * Is it already toasted? + */ + if (rel->rd_rel->reltoastrelid != InvalidOid) + return false; + + /* + * Check to see whether the table actually needs a TOAST table. + */ + if (!IsBinaryUpgrade) + { + /* Normal mode, normal check */ + if (!needs_toast_table(rel)) + return false; + } + else + { + /* + * In binary-upgrade mode, create a TOAST table if and only if + * pg_upgrade told us to (ie, a TOAST table OID has been provided). + * + * This indicates that the old cluster had a TOAST table for the + * current table. We must create a TOAST table to receive the old + * TOAST file, even if the table seems not to need one. + * + * Contrariwise, if the old cluster did not have a TOAST table, we + * should be able to get along without one even if the new version's + * needs_toast_table rules suggest we should have one. There is a lot + * of daylight between where we will create a TOAST table and where + * one is really necessary to avoid failures, so small cross-version + * differences in the when-to-create heuristic shouldn't be a problem. + * If we tried to create a TOAST table anyway, we would have the + * problem that it might take up an OID that will conflict with some + * old-cluster table we haven't seen yet. + */ + if (!OidIsValid(binary_upgrade_next_toast_pg_class_oid)) + return false; + } + + /* + * If requested check lockmode is sufficient. This is a cross check in + * case of errors or conflicting decisions in earlier code. + */ + if (check && lockmode != AccessExclusiveLock) + elog(ERROR, "AccessExclusiveLock required to add toast table."); + + /* + * Create the toast table and its index + */ + snprintf(toast_relname, sizeof(toast_relname), + "pg_toast_%u", relOid); + snprintf(toast_idxname, sizeof(toast_idxname), + "pg_toast_%u_index", relOid); + + /* this is pretty painful... need a tuple descriptor */ + tupdesc = CreateTemplateTupleDesc(3); + TupleDescInitEntry(tupdesc, (AttrNumber) 1, + "chunk_id", + OIDOID, + -1, 0); + TupleDescInitEntry(tupdesc, (AttrNumber) 2, + "chunk_seq", + INT4OID, + -1, 0); + TupleDescInitEntry(tupdesc, (AttrNumber) 3, + "chunk_data", + BYTEAOID, + -1, 0); + + /* + * Ensure that the toast table doesn't itself get toasted, or we'll be + * toast :-(. This is essential for chunk_data because type bytea is + * toastable; hit the other two just to be sure. + */ + TupleDescAttr(tupdesc, 0)->attstorage = TYPSTORAGE_PLAIN; + TupleDescAttr(tupdesc, 1)->attstorage = TYPSTORAGE_PLAIN; + TupleDescAttr(tupdesc, 2)->attstorage = TYPSTORAGE_PLAIN; + + /* Toast field should not be compressed */ + TupleDescAttr(tupdesc, 0)->attcompression = InvalidCompressionMethod; + TupleDescAttr(tupdesc, 1)->attcompression = InvalidCompressionMethod; + TupleDescAttr(tupdesc, 2)->attcompression = InvalidCompressionMethod; + + /* + * Toast tables for regular relations go in pg_toast; those for temp + * relations go into the per-backend temp-toast-table namespace. + */ + if (isTempOrTempToastNamespace(rel->rd_rel->relnamespace)) + namespaceid = GetTempToastNamespace(); + else + namespaceid = PG_TOAST_NAMESPACE; + + /* Toast table is shared if and only if its parent is. */ + shared_relation = rel->rd_rel->relisshared; + + /* It's mapped if and only if its parent is, too */ + mapped_relation = RelationIsMapped(rel); + + toast_relid = heap_create_with_catalog(toast_relname, + namespaceid, + rel->rd_rel->reltablespace, + toastOid, + InvalidOid, + InvalidOid, + rel->rd_rel->relowner, + table_relation_toast_am(rel), + tupdesc, + NIL, + RELKIND_TOASTVALUE, + rel->rd_rel->relpersistence, + shared_relation, + mapped_relation, + ONCOMMIT_NOOP, + reloptions, + false, + true, + true, + OIDOldToast, + NULL); + Assert(toast_relid != InvalidOid); + + /* make the toast relation visible, else table_open will fail */ + CommandCounterIncrement(); + + /* ShareLock is not really needed here, but take it anyway */ + toast_rel = table_open(toast_relid, ShareLock); + + /* + * Create unique index on chunk_id, chunk_seq. + * + * NOTE: the normal TOAST access routines could actually function with a + * single-column index on chunk_id only. However, the slice access + * routines use both columns for faster access to an individual chunk. In + * addition, we want it to be unique as a check against the possibility of + * duplicate TOAST chunk OIDs. The index might also be a little more + * efficient this way, since btree isn't all that happy with large numbers + * of equal keys. + */ + + indexInfo = makeNode(IndexInfo); + indexInfo->ii_NumIndexAttrs = 2; + indexInfo->ii_NumIndexKeyAttrs = 2; + indexInfo->ii_IndexAttrNumbers[0] = 1; + indexInfo->ii_IndexAttrNumbers[1] = 2; + indexInfo->ii_Expressions = NIL; + indexInfo->ii_ExpressionsState = NIL; + indexInfo->ii_Predicate = NIL; + indexInfo->ii_PredicateState = NULL; + indexInfo->ii_ExclusionOps = NULL; + indexInfo->ii_ExclusionProcs = NULL; + indexInfo->ii_ExclusionStrats = NULL; + indexInfo->ii_OpclassOptions = NULL; + indexInfo->ii_Unique = true; + indexInfo->ii_NullsNotDistinct = false; + indexInfo->ii_ReadyForInserts = true; + indexInfo->ii_CheckedUnchanged = false; + indexInfo->ii_IndexUnchanged = false; + indexInfo->ii_Concurrent = false; + indexInfo->ii_BrokenHotChain = false; + indexInfo->ii_ParallelWorkers = 0; + indexInfo->ii_Am = BTREE_AM_OID; + indexInfo->ii_AmCache = NULL; + indexInfo->ii_Context = CurrentMemoryContext; + + collationObjectId[0] = InvalidOid; + collationObjectId[1] = InvalidOid; + + classObjectId[0] = OID_BTREE_OPS_OID; + classObjectId[1] = INT4_BTREE_OPS_OID; + + coloptions[0] = 0; + coloptions[1] = 0; + + index_create(toast_rel, toast_idxname, toastIndexOid, InvalidOid, + InvalidOid, InvalidOid, + indexInfo, + list_make2("chunk_id", "chunk_seq"), + BTREE_AM_OID, + rel->rd_rel->reltablespace, + collationObjectId, classObjectId, coloptions, (Datum) 0, + INDEX_CREATE_IS_PRIMARY, 0, true, true, NULL); + + table_close(toast_rel, NoLock); + + /* + * Store the toast table's OID in the parent relation's pg_class row + */ + class_rel = table_open(RelationRelationId, RowExclusiveLock); + + reltup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relOid)); + if (!HeapTupleIsValid(reltup)) + elog(ERROR, "cache lookup failed for relation %u", relOid); + + ((Form_pg_class) GETSTRUCT(reltup))->reltoastrelid = toast_relid; + + if (!IsBootstrapProcessingMode()) + { + /* normal case, use a transactional update */ + CatalogTupleUpdate(class_rel, &reltup->t_self, reltup); + } + else + { + /* While bootstrapping, we cannot UPDATE, so overwrite in-place */ + heap_inplace_update(class_rel, reltup); + } + + heap_freetuple(reltup); + + table_close(class_rel, RowExclusiveLock); + + /* + * Register dependency from the toast table to the main, so that the toast + * table will be deleted if the main is. Skip this in bootstrap mode. + */ + if (!IsBootstrapProcessingMode()) + { + baseobject.classId = RelationRelationId; + baseobject.objectId = relOid; + baseobject.objectSubId = 0; + toastobject.classId = RelationRelationId; + toastobject.objectId = toast_relid; + toastobject.objectSubId = 0; + + recordDependencyOn(&toastobject, &baseobject, DEPENDENCY_INTERNAL); + } + + /* + * Make changes visible + */ + CommandCounterIncrement(); + + return true; +} + +/* + * Check to see whether the table needs a TOAST table. + */ +static bool +needs_toast_table(Relation rel) +{ + /* + * No need to create a TOAST table for partitioned tables. + */ + if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE) + return false; + + /* + * We cannot allow toasting a shared relation after initdb (because + * there's no way to mark it toasted in other databases' pg_class). + */ + if (rel->rd_rel->relisshared && !IsBootstrapProcessingMode()) + return false; + + /* + * Ignore attempts to create toast tables on catalog tables after initdb. + * Which catalogs get toast tables is explicitly chosen in catalog/pg_*.h. + * (We could get here via some ALTER TABLE command if the catalog doesn't + * have a toast table.) + */ + if (IsCatalogRelation(rel) && !IsBootstrapProcessingMode()) + return false; + + /* Otherwise, let the AM decide. */ + return table_relation_needs_toast_table(rel); +} |