toasting.c File Reference

#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/toasting.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "utils/rel.h"
#include "utils/syscache.h"

Include dependency graph for toasting.c:

Go to the source code of this file.

Functions
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)
void	AlterTableCreateToastTable (Oid relOid, Datum reloptions, LOCKMODE lockmode)
void	NewHeapCreateToastTable (Oid relOid, Datum reloptions, LOCKMODE lockmode, Oid OIDOldToast)
void	NewRelationCreateToastTable (Oid relOid, Datum reloptions)
void	BootstrapToastTable (char *relName, Oid toastOid, Oid toastIndexOid)

Function Documentation

AlterTableCreateToastTable()

void AlterTableCreateToastTable	(	Oid	relOid,
		Datum	reloptions,
		LOCKMODE	lockmode
	)

Definition at line 57 of file toasting.c.

{
    CheckAndCreateToastTable(relOid, reloptions, lockmode, true, InvalidOid);
}

References CheckAndCreateToastTable(), and InvalidOid.

Referenced by ATRewriteCatalogs().

BootstrapToastTable()

void BootstrapToastTable	(	char *	relName,
		Oid	toastOid,
		Oid	toastIndexOid
	)

Definition at line 97 of file toasting.c.

{
    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);
}

References AccessExclusiveLock, create_toast_table(), elog, ERROR, InvalidOid, makeRangeVar(), NoLock, RelationData::rd_rel, table_close(), and table_openrv().

CheckAndCreateToastTable()

static void CheckAndCreateToastTable ( Oid  relOid, Datum  reloptions, LOCKMODE  lockmode, bool  check, Oid  OIDOldToast  )

static

Definition at line 77 of file toasting.c.

{
    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);
}

References create_toast_table(), InvalidOid, NoLock, table_close(), and table_open().

Referenced by AlterTableCreateToastTable(), NewHeapCreateToastTable(), and NewRelationCreateToastTable().

create_toast_table()

static bool create_toast_table ( Relation  rel, Oid  toastOid, Oid  toastIndexOid, Datum  reloptions, LOCKMODE  lockmode, bool  check, Oid  OIDOldToast  )

static

Definition at line 126 of file toasting.c.

{
    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         collationIds[2];
    Oid         opclassIds[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_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;
 
    collationIds[0] = InvalidOid;
    collationIds[1] = InvalidOid;
 
    opclassIds[0] = OID_BTREE_OPS_OID;
    opclassIds[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,
                 collationIds, opclassIds, NULL, coloptions, NULL, (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;
}

References AccessExclusiveLock, Assert, binary_upgrade_next_toast_pg_class_oid, CatalogTupleUpdate(), ObjectAddress::classId, CommandCounterIncrement(), CreateTemplateTupleDesc(), CurrentMemoryContext, DEPENDENCY_INTERNAL, elog, ERROR, GETSTRUCT, GetTempToastNamespace(), heap_create_with_catalog(), heap_freetuple(), heap_inplace_update(), HeapTupleIsValid, IndexInfo::ii_Am, IndexInfo::ii_AmCache, IndexInfo::ii_BrokenHotChain, IndexInfo::ii_CheckedUnchanged, IndexInfo::ii_Concurrent, IndexInfo::ii_Context, IndexInfo::ii_ExclusionOps, IndexInfo::ii_ExclusionProcs, IndexInfo::ii_ExclusionStrats, IndexInfo::ii_Expressions, IndexInfo::ii_ExpressionsState, IndexInfo::ii_IndexAttrNumbers, IndexInfo::ii_IndexUnchanged, IndexInfo::ii_NullsNotDistinct, IndexInfo::ii_NumIndexAttrs, IndexInfo::ii_NumIndexKeyAttrs, IndexInfo::ii_ParallelWorkers, IndexInfo::ii_Predicate, IndexInfo::ii_PredicateState, IndexInfo::ii_ReadyForInserts, IndexInfo::ii_Unique, index_create(), INDEX_CREATE_IS_PRIMARY, InvalidCompressionMethod, InvalidOid, IsBinaryUpgrade, IsBootstrapProcessingMode, isTempOrTempToastNamespace(), list_make2, makeNode, NAMEDATALEN, needs_toast_table(), NIL, NoLock, ObjectAddress::objectId, ObjectIdGetDatum(), ObjectAddress::objectSubId, OidIsValid, ONCOMMIT_NOOP, RelationData::rd_rel, recordDependencyOn(), RelationGetRelid, RelationIsMapped, RowExclusiveLock, SearchSysCacheCopy1, ShareLock, snprintf, HeapTupleData::t_self, table_close(), table_open(), table_relation_toast_am(), TupleDescAttr, and TupleDescInitEntry().

Referenced by BootstrapToastTable(), and CheckAndCreateToastTable().

needs_toast_table()

static bool needs_toast_table ( Relation  rel )

static

Definition at line 385 of file toasting.c.

{
    /*
     * 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);
}

References IsBootstrapProcessingMode, IsCatalogRelation(), RelationData::rd_rel, and table_relation_needs_toast_table().

Referenced by create_toast_table().

NewHeapCreateToastTable()

void NewHeapCreateToastTable	(	Oid	relOid,
		Datum	reloptions,
		LOCKMODE	lockmode,
		Oid	OIDOldToast
	)

Definition at line 63 of file toasting.c.

{
    CheckAndCreateToastTable(relOid, reloptions, lockmode, false, OIDOldToast);
}

References CheckAndCreateToastTable().

Referenced by make_new_heap().

NewRelationCreateToastTable()

void NewRelationCreateToastTable	(	Oid	relOid,
		Datum	reloptions
	)

Definition at line 70 of file toasting.c.

{
    CheckAndCreateToastTable(relOid, reloptions, AccessExclusiveLock, false,
                             InvalidOid);
}

References AccessExclusiveLock, CheckAndCreateToastTable(), and InvalidOid.

Referenced by create_ctas_internal(), and ProcessUtilitySlow().