示例#1
0
/* ----------------
 *		BuildIndexInfo
 *			Construct an IndexInfo record for an open index
 *
 * IndexInfo stores the information about the index that's needed by
 * FormIndexDatum, which is used for both index_build() and later insertion
 * of individual index tuples.	Normally we build an IndexInfo for an index
 * just once per command, and then use it for (potentially) many tuples.
 * ----------------
 */
IndexInfo *
BuildIndexInfo(Relation index)
{
	IndexInfo  *ii = makeNode(IndexInfo);
	Form_pg_index indexStruct = index->rd_index;
	int			i;
	int			numKeys;

	/* check the number of keys, and copy attr numbers into the IndexInfo */
	numKeys = indexStruct->indnatts;
	if (numKeys < 1 || numKeys > INDEX_MAX_KEYS)
		elog(ERROR, "invalid indnatts %d for index %u",
			 numKeys, RelationGetRelid(index));
	ii->ii_NumIndexAttrs = numKeys;
	for (i = 0; i < numKeys; i++)
		ii->ii_KeyAttrNumbers[i] = indexStruct->indkey[i];

	/* fetch any expressions needed for expressional indexes */
	ii->ii_Expressions = RelationGetIndexExpressions(index);
	ii->ii_ExpressionsState = NIL;

	/* fetch index predicate if any */
	ii->ii_Predicate = RelationGetIndexPredicate(index);
	ii->ii_PredicateState = NIL;

	/* other info */
	ii->ii_Unique = indexStruct->indisunique;

	return ii;
}
示例#2
0
/*
 * get_relation_info -
 *	  Retrieves catalog information for a given relation.
 *
 * Given the Oid of the relation, return the following info into fields
 * of the RelOptInfo struct:
 *
 *	min_attr	lowest valid AttrNumber
 *	max_attr	highest valid AttrNumber
 *	indexlist	list of IndexOptInfos for relation's indexes
 *	pages		number of pages
 *	tuples		number of tuples
 *
 * Also, initialize the attr_needed[] and attr_widths[] arrays.  In most
 * cases these are left as zeroes, but sometimes we need to compute attr
 * widths here, and we may as well cache the results for costsize.c.
 *
 * If inhparent is true, all we need to do is set up the attr arrays:
 * the RelOptInfo actually represents the appendrel formed by an inheritance
 * tree, and so the parent rel's physical size and index information isn't
 * important for it.
 */
void
get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
				  RelOptInfo *rel)
{
	Index		varno = rel->relid;
	Relation	relation;
	bool		hasindex;
	List	   *indexinfos = NIL;

	/*
	 * We need not lock the relation since it was already locked, either by
	 * the rewriter or when expand_inherited_rtentry() added it to the query's
	 * rangetable.
	 */
	relation = heap_open(relationObjectId, NoLock);

	rel->min_attr = FirstLowInvalidHeapAttributeNumber + 1;
	rel->max_attr = RelationGetNumberOfAttributes(relation);
	rel->reltablespace = RelationGetForm(relation)->reltablespace;

	Assert(rel->max_attr >= rel->min_attr);
	rel->attr_needed = (Relids *)
		palloc0((rel->max_attr - rel->min_attr + 1) * sizeof(Relids));
	rel->attr_widths = (int32 *)
		palloc0((rel->max_attr - rel->min_attr + 1) * sizeof(int32));

	/*
	 * Estimate relation size --- unless it's an inheritance parent, in which
	 * case the size will be computed later in set_append_rel_pathlist, and we
	 * must leave it zero for now to avoid bollixing the total_table_pages
	 * calculation.
	 */
	if (!inhparent)
		estimate_rel_size(relation, rel->attr_widths - rel->min_attr,
						  &rel->pages, &rel->tuples);

	/*
	 * Make list of indexes.  Ignore indexes on system catalogs if told to.
	 * Don't bother with indexes for an inheritance parent, either.
	 */
	if (inhparent ||
		(IgnoreSystemIndexes && IsSystemClass(relation->rd_rel)))
		hasindex = false;
	else
		hasindex = relation->rd_rel->relhasindex;

	if (hasindex)
	{
		List	   *indexoidlist;
		ListCell   *l;
		LOCKMODE	lmode;

		indexoidlist = RelationGetIndexList(relation);

		/*
		 * For each index, we get the same type of lock that the executor will
		 * need, and do not release it.  This saves a couple of trips to the
		 * shared lock manager while not creating any real loss of
		 * concurrency, because no schema changes could be happening on the
		 * index while we hold lock on the parent rel, and neither lock type
		 * blocks any other kind of index operation.
		 */
		if (rel->relid == root->parse->resultRelation)
			lmode = RowExclusiveLock;
		else
			lmode = AccessShareLock;

		foreach(l, indexoidlist)
		{
			Oid			indexoid = lfirst_oid(l);
			Relation	indexRelation;
			Form_pg_index index;
			IndexOptInfo *info;
			int			ncolumns;
			int			i;

			/*
			 * Extract info from the relation descriptor for the index.
			 */
			indexRelation = index_open(indexoid, lmode);
			index = indexRelation->rd_index;

			/*
			 * Ignore invalid indexes, since they can't safely be used for
			 * queries.  Note that this is OK because the data structure we
			 * are constructing is only used by the planner --- the executor
			 * still needs to insert into "invalid" indexes!
			 */
			if (!index->indisvalid)
			{
				index_close(indexRelation, NoLock);
				continue;
			}

			/*
			 * If the index is valid, but cannot yet be used, ignore it; but
			 * mark the plan we are generating as transient. See
			 * src/backend/access/heap/README.HOT for discussion.
			 */
			if (index->indcheckxmin &&
				!TransactionIdPrecedes(HeapTupleHeaderGetXmin(indexRelation->rd_indextuple->t_data),
									   TransactionXmin))
			{
				root->glob->transientPlan = true;
				index_close(indexRelation, NoLock);
				continue;
			}

			info = makeNode(IndexOptInfo);

			info->indexoid = index->indexrelid;
			info->reltablespace =
				RelationGetForm(indexRelation)->reltablespace;
			info->rel = rel;
			info->ncolumns = ncolumns = index->indnatts;

			/*
			 * Allocate per-column info arrays.  To save a few palloc cycles
			 * we allocate all the Oid-type arrays in one request.	Note that
			 * the opfamily array needs an extra, terminating zero at the end.
			 * We pre-zero the ordering info in case the index is unordered.
			 */
			info->indexkeys = (int *) palloc(sizeof(int) * ncolumns);
			info->opfamily = (Oid *) palloc0(sizeof(Oid) * (4 * ncolumns + 1));
			info->opcintype = info->opfamily + (ncolumns + 1);
			info->fwdsortop = info->opcintype + ncolumns;
			info->revsortop = info->fwdsortop + ncolumns;
			info->nulls_first = (bool *) palloc0(sizeof(bool) * ncolumns);

			for (i = 0; i < ncolumns; i++)
			{
				info->indexkeys[i] = index->indkey.values[i];
				info->opfamily[i] = indexRelation->rd_opfamily[i];
				info->opcintype[i] = indexRelation->rd_opcintype[i];
			}

			info->relam = indexRelation->rd_rel->relam;
			info->amcostestimate = indexRelation->rd_am->amcostestimate;
			info->amoptionalkey = indexRelation->rd_am->amoptionalkey;
			info->amsearchnulls = indexRelation->rd_am->amsearchnulls;
			info->amhasgettuple = OidIsValid(indexRelation->rd_am->amgettuple);
			info->amhasgetbitmap = OidIsValid(indexRelation->rd_am->amgetbitmap);

			/*
			 * Fetch the ordering operators associated with the index, if any.
			 * We expect that all ordering-capable indexes use btree's
			 * strategy numbers for the ordering operators.
			 */
			if (indexRelation->rd_am->amcanorder)
			{
				int			nstrat = indexRelation->rd_am->amstrategies;

				for (i = 0; i < ncolumns; i++)
				{
					int16		opt = indexRelation->rd_indoption[i];
					int			fwdstrat;
					int			revstrat;

					if (opt & INDOPTION_DESC)
					{
						fwdstrat = BTGreaterStrategyNumber;
						revstrat = BTLessStrategyNumber;
					}
					else
					{
						fwdstrat = BTLessStrategyNumber;
						revstrat = BTGreaterStrategyNumber;
					}

					/*
					 * Index AM must have a fixed set of strategies for it to
					 * make sense to specify amcanorder, so we need not allow
					 * the case amstrategies == 0.
					 */
					if (fwdstrat > 0)
					{
						Assert(fwdstrat <= nstrat);
						info->fwdsortop[i] = indexRelation->rd_operator[i * nstrat + fwdstrat - 1];
					}
					if (revstrat > 0)
					{
						Assert(revstrat <= nstrat);
						info->revsortop[i] = indexRelation->rd_operator[i * nstrat + revstrat - 1];
					}
					info->nulls_first[i] = (opt & INDOPTION_NULLS_FIRST) != 0;
				}
			}

			/*
			 * Fetch the index expressions and predicate, if any.  We must
			 * modify the copies we obtain from the relcache to have the
			 * correct varno for the parent relation, so that they match up
			 * correctly against qual clauses.
			 */
			info->indexprs = RelationGetIndexExpressions(indexRelation);
			info->indpred = RelationGetIndexPredicate(indexRelation);
			if (info->indexprs && varno != 1)
				ChangeVarNodes((Node *) info->indexprs, 1, varno, 0);
			if (info->indpred && varno != 1)
				ChangeVarNodes((Node *) info->indpred, 1, varno, 0);
			info->predOK = false;		/* set later in indxpath.c */
			info->unique = index->indisunique;

			/*
			 * Estimate the index size.  If it's not a partial index, we lock
			 * the number-of-tuples estimate to equal the parent table; if it
			 * is partial then we have to use the same methods as we would for
			 * a table, except we can be sure that the index is not larger
			 * than the table.
			 */
			if (info->indpred == NIL)
			{
				info->pages = RelationGetNumberOfBlocks(indexRelation);
				info->tuples = rel->tuples;
			}
			else
			{
				estimate_rel_size(indexRelation, NULL,
								  &info->pages, &info->tuples);
				if (info->tuples > rel->tuples)
					info->tuples = rel->tuples;
			}

			index_close(indexRelation, NoLock);

			indexinfos = lcons(info, indexinfos);
		}

		list_free(indexoidlist);
	}
示例#3
0
文件: plancat.c 项目: a1exsh/postgres
/*
 * get_relation_info -
 *	  Retrieves catalog information for a given relation.
 *
 * Given the Oid of the relation, return the following info into fields
 * of the RelOptInfo struct:
 *
 *	min_attr	lowest valid AttrNumber
 *	max_attr	highest valid AttrNumber
 *	indexlist	list of IndexOptInfos for relation's indexes
 *	pages		number of pages
 *	tuples		number of tuples
 *
 * Also, initialize the attr_needed[] and attr_widths[] arrays.  In most
 * cases these are left as zeroes, but sometimes we need to compute attr
 * widths here, and we may as well cache the results for costsize.c.
 *
 * If inhparent is true, all we need to do is set up the attr arrays:
 * the RelOptInfo actually represents the appendrel formed by an inheritance
 * tree, and so the parent rel's physical size and index information isn't
 * important for it.
 */
void
get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
				  RelOptInfo *rel)
{
	Index		varno = rel->relid;
	Relation	relation;
	bool		hasindex;
	List	   *indexinfos = NIL;

	/*
	 * We need not lock the relation since it was already locked, either by
	 * the rewriter or when expand_inherited_rtentry() added it to the query's
	 * rangetable.
	 */
	relation = heap_open(relationObjectId, NoLock);

	/* Temporary and unlogged relations are inaccessible during recovery. */
	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("cannot access temporary or unlogged relations during recovery")));

	rel->min_attr = FirstLowInvalidHeapAttributeNumber + 1;
	rel->max_attr = RelationGetNumberOfAttributes(relation);
	rel->reltablespace = RelationGetForm(relation)->reltablespace;

	Assert(rel->max_attr >= rel->min_attr);
	rel->attr_needed = (Relids *)
		palloc0((rel->max_attr - rel->min_attr + 1) * sizeof(Relids));
	rel->attr_widths = (int32 *)
		palloc0((rel->max_attr - rel->min_attr + 1) * sizeof(int32));

	/*
	 * Estimate relation size --- unless it's an inheritance parent, in which
	 * case the size will be computed later in set_append_rel_pathlist, and we
	 * must leave it zero for now to avoid bollixing the total_table_pages
	 * calculation.
	 */
	if (!inhparent)
		estimate_rel_size(relation, rel->attr_widths - rel->min_attr,
						  &rel->pages, &rel->tuples, &rel->allvisfrac);

	/*
	 * Make list of indexes.  Ignore indexes on system catalogs if told to.
	 * Don't bother with indexes for an inheritance parent, either.
	 */
	if (inhparent ||
		(IgnoreSystemIndexes && IsSystemClass(relation->rd_rel)))
		hasindex = false;
	else
		hasindex = relation->rd_rel->relhasindex;

	if (hasindex)
	{
		List	   *indexoidlist;
		ListCell   *l;
		LOCKMODE	lmode;

		indexoidlist = RelationGetIndexList(relation);

		/*
		 * For each index, we get the same type of lock that the executor will
		 * need, and do not release it.  This saves a couple of trips to the
		 * shared lock manager while not creating any real loss of
		 * concurrency, because no schema changes could be happening on the
		 * index while we hold lock on the parent rel, and neither lock type
		 * blocks any other kind of index operation.
		 */
		if (rel->relid == root->parse->resultRelation)
			lmode = RowExclusiveLock;
		else
			lmode = AccessShareLock;

		foreach(l, indexoidlist)
		{
			Oid			indexoid = lfirst_oid(l);
			Relation	indexRelation;
			Form_pg_index index;
			IndexOptInfo *info;
			int			ncolumns;
			int			i;

			/*
			 * Extract info from the relation descriptor for the index.
			 */
			indexRelation = index_open(indexoid, lmode);
			index = indexRelation->rd_index;

			/*
			 * Ignore invalid indexes, since they can't safely be used for
			 * queries.  Note that this is OK because the data structure we
			 * are constructing is only used by the planner --- the executor
			 * still needs to insert into "invalid" indexes!
			 */
			if (!index->indisvalid)
			{
				index_close(indexRelation, NoLock);
				continue;
			}

			/*
			 * If the index is valid, but cannot yet be used, ignore it; but
			 * mark the plan we are generating as transient. See
			 * src/backend/access/heap/README.HOT for discussion.
			 */
			if (index->indcheckxmin &&
				!TransactionIdPrecedes(HeapTupleHeaderGetXmin(indexRelation->rd_indextuple->t_data),
									   TransactionXmin))
			{
				root->glob->transientPlan = true;
				index_close(indexRelation, NoLock);
				continue;
			}

			info = makeNode(IndexOptInfo);

			info->indexoid = index->indexrelid;
			info->reltablespace =
				RelationGetForm(indexRelation)->reltablespace;
			info->rel = rel;
			info->ncolumns = ncolumns = index->indnatts;
			info->indexkeys = (int *) palloc(sizeof(int) * ncolumns);
			info->indexcollations = (Oid *) palloc(sizeof(Oid) * ncolumns);
			info->opfamily = (Oid *) palloc(sizeof(Oid) * ncolumns);
			info->opcintype = (Oid *) palloc(sizeof(Oid) * ncolumns);

			for (i = 0; i < ncolumns; i++)
			{
				info->indexkeys[i] = index->indkey.values[i];
				info->indexcollations[i] = indexRelation->rd_indcollation[i];
				info->opfamily[i] = indexRelation->rd_opfamily[i];
				info->opcintype[i] = indexRelation->rd_opcintype[i];
			}

			info->relam = indexRelation->rd_rel->relam;
			info->amcostestimate = indexRelation->rd_am->amcostestimate;
			info->canreturn = index_can_return(indexRelation);
			info->amcanorderbyop = indexRelation->rd_am->amcanorderbyop;
			info->amoptionalkey = indexRelation->rd_am->amoptionalkey;
			info->amsearcharray = indexRelation->rd_am->amsearcharray;
			info->amsearchnulls = indexRelation->rd_am->amsearchnulls;
			info->amhasgettuple = OidIsValid(indexRelation->rd_am->amgettuple);
			info->amhasgetbitmap = OidIsValid(indexRelation->rd_am->amgetbitmap);

			/*
			 * Fetch the ordering information for the index, if any.
			 */
			if (info->relam == BTREE_AM_OID)
			{
				/*
				 * If it's a btree index, we can use its opfamily OIDs
				 * directly as the sort ordering opfamily OIDs.
				 */
				Assert(indexRelation->rd_am->amcanorder);

				info->sortopfamily = info->opfamily;
				info->reverse_sort = (bool *) palloc(sizeof(bool) * ncolumns);
				info->nulls_first = (bool *) palloc(sizeof(bool) * ncolumns);

				for (i = 0; i < ncolumns; i++)
				{
					int16		opt = indexRelation->rd_indoption[i];

					info->reverse_sort[i] = (opt & INDOPTION_DESC) != 0;
					info->nulls_first[i] = (opt & INDOPTION_NULLS_FIRST) != 0;
				}
			}
			else if (indexRelation->rd_am->amcanorder)
			{
				/*
				 * Otherwise, identify the corresponding btree opfamilies by
				 * trying to map this index's "<" operators into btree.  Since
				 * "<" uniquely defines the behavior of a sort order, this is
				 * a sufficient test.
				 *
				 * XXX This method is rather slow and also requires the
				 * undesirable assumption that the other index AM numbers its
				 * strategies the same as btree.  It'd be better to have a way
				 * to explicitly declare the corresponding btree opfamily for
				 * each opfamily of the other index type.  But given the lack
				 * of current or foreseeable amcanorder index types, it's not
				 * worth expending more effort on now.
				 */
				info->sortopfamily = (Oid *) palloc(sizeof(Oid) * ncolumns);
				info->reverse_sort = (bool *) palloc(sizeof(bool) * ncolumns);
				info->nulls_first = (bool *) palloc(sizeof(bool) * ncolumns);

				for (i = 0; i < ncolumns; i++)
				{
					int16		opt = indexRelation->rd_indoption[i];
					Oid			ltopr;
					Oid			btopfamily;
					Oid			btopcintype;
					int16		btstrategy;

					info->reverse_sort[i] = (opt & INDOPTION_DESC) != 0;
					info->nulls_first[i] = (opt & INDOPTION_NULLS_FIRST) != 0;

					ltopr = get_opfamily_member(info->opfamily[i],
												info->opcintype[i],
												info->opcintype[i],
												BTLessStrategyNumber);
					if (OidIsValid(ltopr) &&
						get_ordering_op_properties(ltopr,
												   &btopfamily,
												   &btopcintype,
												   &btstrategy) &&
						btopcintype == info->opcintype[i] &&
						btstrategy == BTLessStrategyNumber)
					{
						/* Successful mapping */
						info->sortopfamily[i] = btopfamily;
					}
					else
					{
						/* Fail ... quietly treat index as unordered */
						info->sortopfamily = NULL;
						info->reverse_sort = NULL;
						info->nulls_first = NULL;
						break;
					}
				}
			}
			else
			{
				info->sortopfamily = NULL;
				info->reverse_sort = NULL;
				info->nulls_first = NULL;
			}

			/*
			 * Fetch the index expressions and predicate, if any.  We must
			 * modify the copies we obtain from the relcache to have the
			 * correct varno for the parent relation, so that they match up
			 * correctly against qual clauses.
			 */
			info->indexprs = RelationGetIndexExpressions(indexRelation);
			info->indpred = RelationGetIndexPredicate(indexRelation);
			if (info->indexprs && varno != 1)
				ChangeVarNodes((Node *) info->indexprs, 1, varno, 0);
			if (info->indpred && varno != 1)
				ChangeVarNodes((Node *) info->indpred, 1, varno, 0);

			/* Build targetlist using the completed indexprs data */
			info->indextlist = build_index_tlist(root, info, relation);

			info->predOK = false;		/* set later in indxpath.c */
			info->unique = index->indisunique;
			info->immediate = index->indimmediate;
			info->hypothetical = false;

			/*
			 * Estimate the index size.  If it's not a partial index, we lock
			 * the number-of-tuples estimate to equal the parent table; if it
			 * is partial then we have to use the same methods as we would for
			 * a table, except we can be sure that the index is not larger
			 * than the table.
			 */
			if (info->indpred == NIL)
			{
				info->pages = RelationGetNumberOfBlocks(indexRelation);
				info->tuples = rel->tuples;
			}
			else
			{
				double		allvisfrac;				/* dummy */

				estimate_rel_size(indexRelation, NULL,
								  &info->pages, &info->tuples, &allvisfrac);
				if (info->tuples > rel->tuples)
					info->tuples = rel->tuples;
			}

			index_close(indexRelation, NoLock);

			indexinfos = lcons(info, indexinfos);
		}

		list_free(indexoidlist);
	}
示例#4
0
文件: matview.c 项目: qowldi/pg
/*
 * refresh_by_match_merge
 *
 * Refresh a materialized view with transactional semantics, while allowing
 * concurrent reads.
 *
 * This is called after a new version of the data has been created in a
 * temporary table.  It performs a full outer join against the old version of
 * the data, producing "diff" results.  This join cannot work if there are any
 * duplicated rows in either the old or new versions, in the sense that every
 * column would compare as equal between the two rows.  It does work correctly
 * in the face of rows which have at least one NULL value, with all non-NULL
 * columns equal.  The behavior of NULLs on equality tests and on UNIQUE
 * indexes turns out to be quite convenient here; the tests we need to make
 * are consistent with default behavior.  If there is at least one UNIQUE
 * index on the materialized view, we have exactly the guarantee we need.
 *
 * The temporary table used to hold the diff results contains just the TID of
 * the old record (if matched) and the ROW from the new table as a single
 * column of complex record type (if matched).
 *
 * Once we have the diff table, we perform set-based DELETE and INSERT
 * operations against the materialized view, and discard both temporary
 * tables.
 *
 * Everything from the generation of the new data to applying the differences
 * takes place under cover of an ExclusiveLock, since it seems as though we
 * would want to prohibit not only concurrent REFRESH operations, but also
 * incremental maintenance.  It also doesn't seem reasonable or safe to allow
 * SELECT FOR UPDATE or SELECT FOR SHARE on rows being updated or deleted by
 * this command.
 */
static void
refresh_by_match_merge(Oid matviewOid, Oid tempOid, Oid relowner,
					   int save_sec_context)
{
	StringInfoData querybuf;
	Relation	matviewRel;
	Relation	tempRel;
	char	   *matviewname;
	char	   *tempname;
	char	   *diffname;
	TupleDesc	tupdesc;
	bool		foundUniqueIndex;
	List	   *indexoidlist;
	ListCell   *indexoidscan;
	int16		relnatts;
	bool	   *usedForQual;

	initStringInfo(&querybuf);
	matviewRel = heap_open(matviewOid, NoLock);
	matviewname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)),
										RelationGetRelationName(matviewRel));
	tempRel = heap_open(tempOid, NoLock);
	tempname = quote_qualified_identifier(get_namespace_name(RelationGetNamespace(tempRel)),
										  RelationGetRelationName(tempRel));
	diffname = make_temptable_name_n(tempname, 2);

	relnatts = matviewRel->rd_rel->relnatts;
	usedForQual = (bool *) palloc0(sizeof(bool) * relnatts);

	/* Open SPI context. */
	if (SPI_connect() != SPI_OK_CONNECT)
		elog(ERROR, "SPI_connect failed");

	/* Analyze the temp table with the new contents. */
	appendStringInfo(&querybuf, "ANALYZE %s", tempname);
	if (SPI_exec(querybuf.data, 0) != SPI_OK_UTILITY)
		elog(ERROR, "SPI_exec failed: %s", querybuf.data);

	/*
	 * We need to ensure that there are not duplicate rows without NULLs in
	 * the new data set before we can count on the "diff" results.  Check for
	 * that in a way that allows showing the first duplicated row found.  Even
	 * after we pass this test, a unique index on the materialized view may
	 * find a duplicate key problem.
	 */
	resetStringInfo(&querybuf);
	appendStringInfo(&querybuf,
					 "SELECT newdata FROM %s newdata "
					 "WHERE newdata IS NOT NULL AND EXISTS "
					 "(SELECT * FROM %s newdata2 WHERE newdata2 IS NOT NULL "
					 "AND newdata2 OPERATOR(pg_catalog.*=) newdata "
					 "AND newdata2.ctid OPERATOR(pg_catalog.<>) "
					 "newdata.ctid) LIMIT 1",
					 tempname, tempname);
	if (SPI_execute(querybuf.data, false, 1) != SPI_OK_SELECT)
		elog(ERROR, "SPI_exec failed: %s", querybuf.data);
	if (SPI_processed > 0)
	{
		ereport(ERROR,
				(errcode(ERRCODE_CARDINALITY_VIOLATION),
				 errmsg("new data for \"%s\" contains duplicate rows without any null columns",
						RelationGetRelationName(matviewRel)),
				 errdetail("Row: %s",
			SPI_getvalue(SPI_tuptable->vals[0], SPI_tuptable->tupdesc, 1))));
	}

	SetUserIdAndSecContext(relowner,
						   save_sec_context | SECURITY_LOCAL_USERID_CHANGE);

	/* Start building the query for creating the diff table. */
	resetStringInfo(&querybuf);
	appendStringInfo(&querybuf,
					 "CREATE TEMP TABLE %s AS "
					 "SELECT mv.ctid AS tid, newdata "
					 "FROM %s mv FULL JOIN %s newdata ON (",
					 diffname, matviewname, tempname);

	/*
	 * Get the list of index OIDs for the table from the relcache, and look up
	 * each one in the pg_index syscache.  We will test for equality on all
	 * columns present in all unique indexes which only reference columns and
	 * include all rows.
	 */
	tupdesc = matviewRel->rd_att;
	foundUniqueIndex = false;
	indexoidlist = RelationGetIndexList(matviewRel);

	foreach(indexoidscan, indexoidlist)
	{
		Oid			indexoid = lfirst_oid(indexoidscan);
		Relation	indexRel;
		Form_pg_index indexStruct;

		indexRel = index_open(indexoid, RowExclusiveLock);
		indexStruct = indexRel->rd_index;

		/*
		 * We're only interested if it is unique, valid, contains no
		 * expressions, and is not partial.
		 */
		if (indexStruct->indisunique &&
			IndexIsValid(indexStruct) &&
			RelationGetIndexExpressions(indexRel) == NIL &&
			RelationGetIndexPredicate(indexRel) == NIL)
		{
			int			numatts = indexStruct->indnatts;
			int			i;

			/* Add quals for all columns from this index. */
			for (i = 0; i < numatts; i++)
			{
				int			attnum = indexStruct->indkey.values[i];
				Oid			type;
				Oid			op;
				const char *colname;

				/*
				 * Only include the column once regardless of how many times
				 * it shows up in how many indexes.
				 */
				if (usedForQual[attnum - 1])
					continue;
				usedForQual[attnum - 1] = true;

				/*
				 * Actually add the qual, ANDed with any others.
				 */
				if (foundUniqueIndex)
					appendStringInfoString(&querybuf, " AND ");

				colname = quote_identifier(NameStr((tupdesc->attrs[attnum - 1])->attname));
				appendStringInfo(&querybuf, "newdata.%s ", colname);
				type = attnumTypeId(matviewRel, attnum);
				op = lookup_type_cache(type, TYPECACHE_EQ_OPR)->eq_opr;
				mv_GenerateOper(&querybuf, op);
				appendStringInfo(&querybuf, " mv.%s", colname);

				foundUniqueIndex = true;
			}
		}

		/* Keep the locks, since we're about to run DML which needs them. */
		index_close(indexRel, NoLock);
	}
示例#5
0
/*
 * get_relation_info -
 *	  Retrieves catalog information for a given relation.
 *
 * Given the Oid of the relation, return the following info into fields
 * of the RelOptInfo struct:
 *
 *	min_attr	lowest valid AttrNumber
 *	max_attr	highest valid AttrNumber
 *	indexlist	list of IndexOptInfos for relation's indexes
 *	pages		number of pages
 *	tuples		number of tuples
 *
 * Also, initialize the attr_needed[] and attr_widths[] arrays.  In most
 * cases these are left as zeroes, but sometimes we need to compute attr
 * widths here, and we may as well cache the results for costsize.c.
 */
void
get_relation_info(Oid relationObjectId, RelOptInfo *rel)
{
	Index		varno = rel->relid;
	Relation	relation;
	bool		hasindex;
	List	   *indexinfos = NIL;

	/*
	 * Normally, we can assume the rewriter already acquired at least
	 * AccessShareLock on each relation used in the query.	However this will
	 * not be the case for relations added to the query because they are
	 * inheritance children of some relation mentioned explicitly. For them,
	 * this is the first access during the parse/rewrite/plan pipeline, and so
	 * we need to obtain and keep a suitable lock.
	 *
	 * XXX really, a suitable lock is RowShareLock if the relation is an
	 * UPDATE/DELETE target, and AccessShareLock otherwise.  However we cannot
	 * easily tell here which to get, so for the moment just get
	 * AccessShareLock always.	The executor will get the right lock when it
	 * runs, which means there is a very small chance of deadlock trying to
	 * upgrade our lock.
	 */
	if (rel->reloptkind == RELOPT_BASEREL)
		relation = heap_open(relationObjectId, NoLock);
	else
		relation = heap_open(relationObjectId, AccessShareLock);

	rel->min_attr = FirstLowInvalidHeapAttributeNumber + 1;
	rel->max_attr = RelationGetNumberOfAttributes(relation);

	Assert(rel->max_attr >= rel->min_attr);
	rel->attr_needed = (Relids *)
		palloc0((rel->max_attr - rel->min_attr + 1) * sizeof(Relids));
	rel->attr_widths = (int32 *)
		palloc0((rel->max_attr - rel->min_attr + 1) * sizeof(int32));

	/*
	 * Estimate relation size.
	 */
	estimate_rel_size(relation, rel->attr_widths - rel->min_attr,
					  &rel->pages, &rel->tuples);

	/*
	 * Make list of indexes.  Ignore indexes on system catalogs if told to.
	 */
	if (IsIgnoringSystemIndexes() && IsSystemClass(relation->rd_rel))
		hasindex = false;
	else
		hasindex = relation->rd_rel->relhasindex;

	if (hasindex)
	{
		List	   *indexoidlist;
		ListCell   *l;

		indexoidlist = RelationGetIndexList(relation);

		foreach(l, indexoidlist)
		{
			Oid			indexoid = lfirst_oid(l);
			Relation	indexRelation;
			Form_pg_index index;
			IndexOptInfo *info;
			int			ncolumns;
			int			i;
			int16		amorderstrategy;

			/*
			 * Extract info from the relation descriptor for the index.
			 *
			 * Note that we take no lock on the index; we assume our lock on
			 * the parent table will protect the index's schema information.
			 * When and if the executor actually uses the index, it will take
			 * a lock as needed to protect the access to the index contents.
			 */
			indexRelation = index_open(indexoid);
			index = indexRelation->rd_index;

			info = makeNode(IndexOptInfo);

			info->indexoid = index->indexrelid;
			info->rel = rel;
			info->ncolumns = ncolumns = index->indnatts;

			/*
			 * Need to make classlist and ordering arrays large enough to put
			 * a terminating 0 at the end of each one.
			 */
			info->indexkeys = (int *) palloc(sizeof(int) * ncolumns);
			info->classlist = (Oid *) palloc0(sizeof(Oid) * (ncolumns + 1));
			info->ordering = (Oid *) palloc0(sizeof(Oid) * (ncolumns + 1));

			for (i = 0; i < ncolumns; i++)
			{
				info->classlist[i] = indexRelation->rd_indclass->values[i];
				info->indexkeys[i] = index->indkey.values[i];
			}

			info->relam = indexRelation->rd_rel->relam;
			info->amcostestimate = indexRelation->rd_am->amcostestimate;
			info->amoptionalkey = indexRelation->rd_am->amoptionalkey;

			/*
			 * Fetch the ordering operators associated with the index, if any.
			 */
			amorderstrategy = indexRelation->rd_am->amorderstrategy;
			if (amorderstrategy != 0)
			{
				int			oprindex = amorderstrategy - 1;

				for (i = 0; i < ncolumns; i++)
				{
					info->ordering[i] = indexRelation->rd_operator[oprindex];
					oprindex += indexRelation->rd_am->amstrategies;
				}
			}

			/*
			 * Fetch the index expressions and predicate, if any.  We must
			 * modify the copies we obtain from the relcache to have the
			 * correct varno for the parent relation, so that they match up
			 * correctly against qual clauses.
			 */
			info->indexprs = RelationGetIndexExpressions(indexRelation);
			info->indpred = RelationGetIndexPredicate(indexRelation);
			if (info->indexprs && varno != 1)
				ChangeVarNodes((Node *) info->indexprs, 1, varno, 0);
			if (info->indpred && varno != 1)
				ChangeVarNodes((Node *) info->indpred, 1, varno, 0);
			info->predOK = false;		/* set later in indxpath.c */
			info->unique = index->indisunique;

			/*
			 * Estimate the index size.  If it's not a partial index, we lock
			 * the number-of-tuples estimate to equal the parent table; if it
			 * is partial then we have to use the same methods as we would for
			 * a table, except we can be sure that the index is not larger
			 * than the table.
			 */
			if (info->indpred == NIL)
			{
				info->pages = RelationGetNumberOfBlocks(indexRelation);
				info->tuples = rel->tuples;
			}
			else
			{
				estimate_rel_size(indexRelation, NULL,
								  &info->pages, &info->tuples);
				if (info->tuples > rel->tuples)
					info->tuples = rel->tuples;
			}

			index_close(indexRelation);

			indexinfos = lcons(info, indexinfos);
		}

		list_free(indexoidlist);
	}
示例#6
0
/*
 * get_relation_info -
 *	  Retrieves catalog information for a given relation.
 *
 * Given the Oid of the relation, return the following info into fields
 * of the RelOptInfo struct:
 *
 *	min_attr	lowest valid AttrNumber
 *	max_attr	highest valid AttrNumber
 *	indexlist	list of IndexOptInfos for relation's indexes
 *	pages		number of pages
 *	tuples		number of tuples
 *
 * Also, initialize the attr_needed[] and attr_widths[] arrays.  In most
 * cases these are left as zeroes, but sometimes we need to compute attr
 * widths here, and we may as well cache the results for costsize.c.
 *
 * If inhparent is true, all we need to do is set up the attr arrays:
 * the RelOptInfo actually represents the appendrel formed by an inheritance
 * tree, and so the parent rel's physical size and index information isn't
 * important for it.
 */
void
get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
				  RelOptInfo *rel)
{
	Index		varno = rel->relid;
	Relation	relation;
	bool		hasindex;
	List	   *indexinfos = NIL;
	bool		needs_longlock;

	/*
	 * We need not lock the relation since it was already locked, either by
	 * the rewriter or when expand_inherited_rtentry() added it to the query's
	 * rangetable.
	 */
	relation = heap_open(relationObjectId, NoLock);
	needs_longlock = rel_needs_long_lock(relationObjectId);

	rel->min_attr = FirstLowInvalidHeapAttributeNumber + 1;
	rel->max_attr = RelationGetNumberOfAttributes(relation);

	Assert(rel->max_attr >= rel->min_attr);
	rel->attr_needed = (Relids *)
		palloc0((rel->max_attr - rel->min_attr + 1) * sizeof(Relids));
	rel->attr_widths = (int32 *)
		palloc0((rel->max_attr - rel->min_attr + 1) * sizeof(int32));

    /*
     * CDB: Get partitioning key info for distributed relation.
     */
    rel->cdbpolicy = RelationGetPartitioningKey(relation);

    /*
     * Estimate relation size --- unless it's an inheritance parent, in which
     * case the size will be computed later in set_append_rel_pathlist, and we
     * must leave it zero for now to avoid bollixing the total_table_pages
     * calculation.
     */
     if (!inhparent)
     {
    	cdb_estimate_rel_size
    		(
    		rel,
    		relation,
    		relation,
    		rel->attr_widths - rel->min_attr,
    		&rel->pages,
    		&rel->tuples,
    		&rel->cdb_default_stats_used
    		);
     }

	/*
	 * Make list of indexes.  Ignore indexes on system catalogs if told to.
	 * Don't bother with indexes for an inheritance parent, either.
	 */
	if (inhparent ||
		(IgnoreSystemIndexes && IsSystemClass(relation->rd_rel)))
		hasindex = false;
	else
		hasindex = relation->rd_rel->relhasindex;

	if (hasindex)
	{
		List	   *indexoidlist;
		ListCell   *l;
		LOCKMODE	lmode;

        /* Warn if indexed table needs ANALYZE. */
        if (rel->cdb_default_stats_used)
            cdb_default_stats_warning_for_table(relation->rd_id);

		indexoidlist = RelationGetIndexList(relation);

		/*
		 * For each index, we get the same type of lock that the executor will
		 * need, and do not release it.  This saves a couple of trips to the
		 * shared lock manager while not creating any real loss of
		 * concurrency, because no schema changes could be happening on the
		 * index while we hold lock on the parent rel, and neither lock type
		 * blocks any other kind of index operation.
		 */
		if (rel->relid == root->parse->resultRelation)
			lmode = RowExclusiveLock;
		else
			lmode = AccessShareLock;

		foreach(l, indexoidlist)
		{
			Oid			indexoid = lfirst_oid(l);
			Relation	indexRelation;
			Form_pg_index index;
			IndexOptInfo *info;
			int			ncolumns;
			int			i;
			int16		amorderstrategy;

			/*
			 * Extract info from the relation descriptor for the index.
			 */
			indexRelation = index_open(indexoid, lmode);
			index = indexRelation->rd_index;

			/*
			 * Ignore invalid indexes, since they can't safely be used for
			 * queries.  Note that this is OK because the data structure we
			 * are constructing is only used by the planner --- the executor
			 * still needs to insert into "invalid" indexes!
			 */
			if (!index->indisvalid)
			{
				index_close(indexRelation, NoLock);
				continue;
			}

			info = makeNode(IndexOptInfo);

			info->indexoid = index->indexrelid;
			info->rel = rel;
			info->ncolumns = ncolumns = index->indnatts;

			/*
			 * Need to make classlist and ordering arrays large enough to put
			 * a terminating 0 at the end of each one.
			 */
			info->indexkeys = (int *) palloc(sizeof(int) * ncolumns);
			info->classlist = (Oid *) palloc0(sizeof(Oid) * (ncolumns + 1));
			info->ordering = (Oid *) palloc0(sizeof(Oid) * (ncolumns + 1));

			for (i = 0; i < ncolumns; i++)
			{
				info->classlist[i] = indexRelation->rd_indclass->values[i];
				info->indexkeys[i] = index->indkey.values[i];
			}

			info->relam = indexRelation->rd_rel->relam;
			info->amcostestimate = indexRelation->rd_am->amcostestimate;
			info->amoptionalkey = indexRelation->rd_am->amoptionalkey;

			/*
			 * Fetch the ordering operators associated with the index, if any.
			 */
			amorderstrategy = indexRelation->rd_am->amorderstrategy;
			if (amorderstrategy != 0)
			{
				int			oprindex = amorderstrategy - 1;

				for (i = 0; i < ncolumns; i++)
				{
					info->ordering[i] = indexRelation->rd_operator[oprindex];
					oprindex += indexRelation->rd_am->amstrategies;
				}
			}

			/*
			 * Fetch the index expressions and predicate, if any.  We must
			 * modify the copies we obtain from the relcache to have the
			 * correct varno for the parent relation, so that they match up
			 * correctly against qual clauses.
			 */
			info->indexprs = RelationGetIndexExpressions(indexRelation);
			info->indpred = RelationGetIndexPredicate(indexRelation);
			if (info->indexprs && varno != 1)
				ChangeVarNodes((Node *) info->indexprs, 1, varno, 0);
			if (info->indpred && varno != 1)
				ChangeVarNodes((Node *) info->indpred, 1, varno, 0);
			info->predOK = false;		/* set later in indxpath.c */
			info->unique = index->indisunique;

			/*
			 * Estimate the index size.  If it's not a partial index, we lock
			 * the number-of-tuples estimate to equal the parent table; if it
			 * is partial then we have to use the same methods as we would for
			 * a table, except we can be sure that the index is not larger
			 * than the table.
			 */
			cdb_estimate_rel_size(rel,
                                  relation,
                                  indexRelation,
                                  NULL,
                                  &info->pages,
                                  &info->tuples,
                                  &info->cdb_default_stats_used);

			if (!info->indpred ||
				info->tuples > rel->tuples)
				info->tuples = rel->tuples;

            if (info->cdb_default_stats_used &&
                !rel->cdb_default_stats_used)
                cdb_default_stats_warning_for_index(relation->rd_id, indexoid);

			index_close(indexRelation, needs_longlock ? NoLock : lmode);

			indexinfos = lcons(info, indexinfos);
		}

		list_free(indexoidlist);
	}
示例#7
0
/*
 * ExecRefreshMatView -- execute a REFRESH MATERIALIZED VIEW command
 *
 * This refreshes the materialized view by creating a new table and swapping
 * the relfilenodes of the new table and the old materialized view, so the OID
 * of the original materialized view is preserved. Thus we do not lose GRANT
 * nor references to this materialized view.
 *
 * If WITH NO DATA was specified, this is effectively like a TRUNCATE;
 * otherwise it is like a TRUNCATE followed by an INSERT using the SELECT
 * statement associated with the materialized view.  The statement node's
 * skipData field shows whether the clause was used.
 *
 * Indexes are rebuilt too, via REINDEX. Since we are effectively bulk-loading
 * the new heap, it's better to create the indexes afterwards than to fill them
 * incrementally while we load.
 *
 * The matview's "populated" state is changed based on whether the contents
 * reflect the result set of the materialized view's query.
 */
ObjectAddress
ExecRefreshMatView(RefreshMatViewStmt *stmt, const char *queryString,
				   ParamListInfo params, char *completionTag)
{
	Oid			matviewOid;
	Relation	matviewRel;
	RewriteRule *rule;
	List	   *actions;
	Query	   *dataQuery;
	Oid			tableSpace;
	Oid			relowner;
	Oid			OIDNewHeap;
	DestReceiver *dest;
	bool		concurrent;
	LOCKMODE	lockmode;
	char		relpersistence;
	Oid			save_userid;
	int			save_sec_context;
	int			save_nestlevel;
	ObjectAddress address;

	/* Determine strength of lock needed. */
	concurrent = stmt->concurrent;
	lockmode = concurrent ? ExclusiveLock : AccessExclusiveLock;

	/*
	 * Get a lock until end of transaction.
	 */
	matviewOid = RangeVarGetRelidExtended(stmt->relation,
										  lockmode, false, false,
										  RangeVarCallbackOwnsTable, NULL);
	matviewRel = heap_open(matviewOid, NoLock);

	/* Make sure it is a materialized view. */
	if (matviewRel->rd_rel->relkind != RELKIND_MATVIEW)
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("\"%s\" is not a materialized view",
						RelationGetRelationName(matviewRel))));

	/* Check that CONCURRENTLY is not specified if not populated. */
	if (concurrent && !RelationIsPopulated(matviewRel))
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("CONCURRENTLY cannot be used when the materialized view is not populated")));

	/* Check that conflicting options have not been specified. */
	if (concurrent && stmt->skipData)
		ereport(ERROR,
				(errcode(ERRCODE_SYNTAX_ERROR),
				 errmsg("CONCURRENTLY and WITH NO DATA options cannot be used together")));

	/* We don't allow an oid column for a materialized view. */
	Assert(!matviewRel->rd_rel->relhasoids);

	/*
	 * Check that everything is correct for a refresh. Problems at this point
	 * are internal errors, so elog is sufficient.
	 */
	if (matviewRel->rd_rel->relhasrules == false ||
		matviewRel->rd_rules->numLocks < 1)
		elog(ERROR,
			 "materialized view \"%s\" is missing rewrite information",
			 RelationGetRelationName(matviewRel));

	if (matviewRel->rd_rules->numLocks > 1)
		elog(ERROR,
			 "materialized view \"%s\" has too many rules",
			 RelationGetRelationName(matviewRel));

	rule = matviewRel->rd_rules->rules[0];
	if (rule->event != CMD_SELECT || !(rule->isInstead))
		elog(ERROR,
			 "the rule for materialized view \"%s\" is not a SELECT INSTEAD OF rule",
			 RelationGetRelationName(matviewRel));

	actions = rule->actions;
	if (list_length(actions) != 1)
		elog(ERROR,
			 "the rule for materialized view \"%s\" is not a single action",
			 RelationGetRelationName(matviewRel));

	/*
	 * Check that there is a unique index with no WHERE clause on
	 * one or more columns of the materialized view if CONCURRENTLY
	 * is specified.
	 */
	if (concurrent)
	{
		List		*indexoidlist = RelationGetIndexList(matviewRel);
		ListCell 	*indexoidscan;
		bool		hasUniqueIndex = false;

		foreach(indexoidscan, indexoidlist)
		{
			Oid			indexoid = lfirst_oid(indexoidscan);
			Relation	indexRel;
			Form_pg_index	indexStruct;

			indexRel = index_open(indexoid, AccessShareLock);
			indexStruct = indexRel->rd_index;

			if (indexStruct->indisunique &&
				IndexIsValid(indexStruct) &&
				RelationGetIndexExpressions(indexRel) == NIL &&
				RelationGetIndexPredicate(indexRel) == NIL &&
				indexStruct->indnatts > 0)
			{
				hasUniqueIndex = true;
				index_close(indexRel, AccessShareLock);
				break;
			}

			index_close(indexRel, AccessShareLock);
		}

		list_free(indexoidlist);

		if (!hasUniqueIndex)
			ereport(ERROR,
					(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
					 errmsg("cannot refresh materialized view \"%s\" concurrently",
							quote_qualified_identifier(get_namespace_name(RelationGetNamespace(matviewRel)),
													   RelationGetRelationName(matviewRel))),
					 errhint("Create a unique index with no WHERE clause on one or more columns of the materialized view.")));
	}