executils.c

关系型数据库 Postgresql 6.5.2

		 * ----------------
		 */
		if (VARSIZE(&indexStruct->indpred) != 0)
		{
			predString = fmgr(F_TEXTOUT, &indexStruct->indpred);
			predicate = (PredInfo *) stringToNode(predString);
			pfree(predString);
		}
		else
			predicate = NULL;

		/* ----------------
		 *	save the index information into lists
		 * ----------------
		 */
		oidList = lconsi(indexOid, oidList);
		nkeyList = lconsi(numKeyAtts, nkeyList);
		keyList = lcons(indexKeyAtts, keyList);
		fiList = lcons(fInfoP, fiList);
		predList = lcons(predicate, predList);
	}

	/* ----------------
	 *	we have the info we need so close the pg_index relation..
	 * ----------------
	 */
	heap_endscan(indexSd);
	heap_close(indexRd);

	/* ----------------
	 *	Now that we've collected the index information into three
	 *	lists, we open the index relations and store the descriptors
	 *	and the key information into arrays.
	 * ----------------
	 */
	len = length(oidList);
	if (len > 0)
	{
		/* ----------------
		 *	 allocate space for relation descs
		 * ----------------
		 */
		CXT1_printf("ExecOpenIndices: context is %d\n", CurrentMemoryContext);
		relationDescs = (RelationPtr)
			palloc(len * sizeof(Relation));

		/* ----------------
		 *	 initialize index info array
		 * ----------------
		 */
		CXT1_printf("ExecOpenIndices: context is %d\n", CurrentMemoryContext);
		indexInfoArray = (IndexInfo **)
			palloc(len * sizeof(IndexInfo *));

		for (i = 0; i < len; i++)
		{
			IndexInfo  *ii = makeNode(IndexInfo);

			ii->ii_NumKeyAttributes = 0;
			ii->ii_KeyAttributeNumbers = (AttrNumber *) NULL;
			ii->ii_FuncIndexInfo = (FuncIndexInfoPtr) NULL;
			ii->ii_Predicate = NULL;
			indexInfoArray[i] = ii;
		}

		/* ----------------
		 *	 attempt to open each of the indices.  If we succeed,
		 *	 then store the index relation descriptor into the
		 *	 relation descriptor array.
		 * ----------------
		 */
		i = 0;
		foreach(indexoid, oidList)
		{
			Relation	indexDesc;

			indexOid = lfirsti(indexoid);
			indexDesc = index_open(indexOid);
			if (indexDesc != NULL)
			{
				relationDescs[i++] = indexDesc;

				/*
				 * Hack for not btree and hash indices: they use relation
				 * level exclusive locking on updation (i.e. - they are
				 * not ready for MVCC) and so we have to exclusively lock
				 * indices here to prevent deadlocks if we will scan them
				 * - index_beginscan places AccessShareLock, indices
				 * update methods don't use locks at all. We release this
				 * lock in ExecCloseIndices. Note, that hashes use page
				 * level locking - i.e. are not deadlock-free, - let's
				 * them be on their way -:)) vadim 03-12-1998
				 */
				if (indexDesc->rd_rel->relam != BTREE_AM_OID &&
					indexDesc->rd_rel->relam != HASH_AM_OID)
					LockRelation(indexDesc, AccessExclusiveLock);
			}
		}

		/* ----------------
		 *	 store the relation descriptor array and number of
		 *	 descs into the result relation info.
		 * ----------------
		 */
		resultRelationInfo->ri_NumIndices = i;
		resultRelationInfo->ri_IndexRelationDescs = relationDescs;

		/* ----------------
		 *	 store the index key information collected in our
		 *	 lists into the index info array
		 * ----------------
		 */
		i = 0;
		foreach(numkeys, nkeyList)
		{
			numKeyAtts = lfirsti(numkeys);
			indexInfoArray[i++]->ii_NumKeyAttributes = numKeyAtts;
		}

		i = 0;
		foreach(indexkeys, keyList)
		{
			indexKeyAtts = (AttrNumber *) lfirst(indexkeys);
			indexInfoArray[i++]->ii_KeyAttributeNumbers = indexKeyAtts;
		}

		i = 0;
		foreach(indexfuncs, fiList)
		{
			FuncIndexInfoPtr fiP = (FuncIndexInfoPtr) lfirst(indexfuncs);

			indexInfoArray[i++]->ii_FuncIndexInfo = fiP;
		}

		i = 0;
		foreach(indexpreds, predList)
			indexInfoArray[i++]->ii_Predicate = lfirst(indexpreds);
		/* ----------------
		 *	 store the index info array into relation info
		 * ----------------
		 */
		resultRelationInfo->ri_IndexRelationInfo = indexInfoArray;
	}

	/* ----------------
	 *	All done,  resultRelationInfo now contains complete information
	 *	on the indices associated with the result relation.
	 * ----------------
	 */

	/* should free oidList, nkeyList and keyList here */
	/* OK - let's do it   -jolly */
	freeList(oidList);
	freeList(nkeyList);
	freeList(keyList);
	freeList(fiList);
	freeList(predList);
}

/* ----------------------------------------------------------------
 *		ExecCloseIndices
 *
 *		Close the index relations stored in resultRelationInfo
 * ----------------------------------------------------------------
 */
void
ExecCloseIndices(RelationInfo *resultRelationInfo)
{
	int			i;
	int			numIndices;
	RelationPtr relationDescs;

	numIndices = resultRelationInfo->ri_NumIndices;
	relationDescs = resultRelationInfo->ri_IndexRelationDescs;

	for (i = 0; i < numIndices; i++)
	{
		if (relationDescs[i] == NULL)
			continue;

		/*
		 * Notes in ExecOpenIndices.
		 */
		if (relationDescs[i]->rd_rel->relam != BTREE_AM_OID &&
			relationDescs[i]->rd_rel->relam != HASH_AM_OID)
			UnlockRelation(relationDescs[i], AccessExclusiveLock);

		index_close(relationDescs[i]);
	}

	/*
	 * XXX should free indexInfo array here too.
	 */
}

/* ----------------------------------------------------------------
 *		ExecFormIndexTuple
 *
 *		Most of this code is cannabilized from DefaultBuild().
 *		As said in the comments for ExecOpenIndices, most of
 *		this functionality should be rearranged into a proper
 *		set of routines..
 * ----------------------------------------------------------------
 */
#ifdef NOT_USED
IndexTuple
ExecFormIndexTuple(HeapTuple heapTuple,
				   Relation heapRelation,
				   Relation indexRelation,
				   IndexInfo *indexInfo)
{
	IndexTuple	indexTuple;
	TupleDesc	heapDescriptor;
	TupleDesc	indexDescriptor;
	Datum	   *datum;
	char	   *nulls;

	int			numberOfAttributes;
	AttrNumber *keyAttributeNumbers;
	FuncIndexInfoPtr fInfoP;

	/* ----------------
	 *	get information from index info structure
	 * ----------------
	 */
	numberOfAttributes = indexInfo->ii_NumKeyAttributes;
	keyAttributeNumbers = indexInfo->ii_KeyAttributeNumbers;
	fInfoP = indexInfo->ii_FuncIndexInfo;

	/* ----------------
	 *	datum and null are arrays in which we collect the index attributes
	 *	when forming a new index tuple.
	 * ----------------
	 */
	CXT1_printf("ExecFormIndexTuple: context is %d\n", CurrentMemoryContext);
	datum = (Datum *) palloc(numberOfAttributes * sizeof *datum);
	nulls = (char *) palloc(numberOfAttributes * sizeof *nulls);

	/* ----------------
	 *	get the tuple descriptors from the relations so we know
	 *	how to form the index tuples..
	 * ----------------
	 */
	heapDescriptor = RelationGetDescr(heapRelation);
	indexDescriptor = RelationGetDescr(indexRelation);

	/* ----------------
	 *	FormIndexDatum fills in its datum and null parameters
	 *	with attribute information taken from the given heap tuple.
	 * ----------------
	 */
	FormIndexDatum(numberOfAttributes,	/* num attributes */
				   keyAttributeNumbers, /* array of att nums to extract */
				   heapTuple,	/* tuple from base relation */
				   heapDescriptor,		/* heap tuple's descriptor */
				   datum,		/* return: array of attributes */
				   nulls,		/* return: array of char's */
				   fInfoP);		/* functional index information */

	indexTuple = index_formtuple(indexDescriptor,
								 datum,
								 nulls);

	/* ----------------
	 *	free temporary arrays
	 *
	 *	XXX should store these in the IndexInfo instead of allocating
	 *	   and freeing on every insertion, but efficency here is not
	 *	   that important and FormIndexTuple is wasteful anyways..
	 *	   -cim 9/27/89
	 * ----------------
	 */
	pfree(nulls);
	pfree(datum);

	return indexTuple;
}

#endif

/* ----------------------------------------------------------------
 *		ExecInsertIndexTuples
 *
 *		This routine takes care of inserting index tuples
 *		into all the relations indexing the result relation
 *		when a heap tuple is inserted into the result relation.
 *		Much of this code should be moved into the genam
 *		stuff as it only exists here because the genam stuff
 *		doesn't provide the functionality needed by the
 *		executor.. -cim 9/27/89
 * ----------------------------------------------------------------
 */
void
ExecInsertIndexTuples(TupleTableSlot *slot,
					  ItemPointer tupleid,
					  EState *estate,
					  bool is_update)
{
	HeapTuple	heapTuple;
	RelationInfo *resultRelationInfo;
	int			i;
	int			numIndices;
	RelationPtr relationDescs;
	Relation	heapRelation;
	IndexInfo **indexInfoArray;
	IndexInfo  *indexInfo;
	Node	   *predicate;
	bool		satisfied;
	ExprContext *econtext;
	InsertIndexResult result;
	int			numberOfAttributes;
	AttrNumber *keyAttributeNumbers;
	FuncIndexInfoPtr fInfoP;
	TupleDesc	heapDescriptor;
	Datum	   *datum;
	char	   *nulls;

	heapTuple = slot->val;

	/* ----------------
	 *	get information from the result relation info structure.
	 * ----------------
	 */
	resultRelationInfo = estate->es_result_relation_info;
	numIndices = resultRelationInfo->ri_NumIndices;
	relationDescs = resultRelationInfo->ri_IndexRelationDescs;
	indexInfoArray = resultRelationInfo->ri_IndexRelationInfo;
	heapRelation = resultRelationInfo->ri_RelationDesc;

	/* ----------------
	 *	for each index, form and insert the index tuple
	 * ----------------
	 */
	econtext = NULL;
	for (i = 0; i < numIndices; i++)
	{
		if (relationDescs[i] == NULL)
			continue;

		indexInfo = indexInfoArray[i];
		predicate = indexInfo->ii_Predicate;
		if (predicate != NULL)
		{
			if (econtext == NULL)
				econtext = makeNode(ExprContext);
			econtext->ecxt_scantuple = slot;

			/* Skip this index-update if the predicate isn't satisfied */
			satisfied = ExecQual((List *) predicate, econtext);
			if (satisfied == false)
				continue;
		}

		/* ----------------
		 *		get information from index info structure
		 * ----------------
		 */
		numberOfAttributes = indexInfo->ii_NumKeyAttributes;
		keyAttributeNumbers = indexInfo->ii_KeyAttributeNumbers;
		fInfoP = indexInfo->ii_FuncIndexInfo;
		datum = (Datum *) palloc(numberOfAttributes * sizeof *datum);
		nulls = (char *) palloc(numberOfAttributes * sizeof *nulls);
		heapDescriptor = (TupleDesc) RelationGetDescr(heapRelation);

		FormIndexDatum(numberOfAttributes,		/* num attributes */
					   keyAttributeNumbers,		/* array of att nums to
												 * extract */
					   heapTuple,		/* tuple from base relation */
					   heapDescriptor,	/* heap tuple's descriptor */
					   datum,	/* return: array of attributes */
					   nulls,	/* return: array of char's */
					   fInfoP); /* functional index information */


		result = index_insert(relationDescs[i], /* index relation */
							  datum,	/* array of heaptuple Datums */
							  nulls,	/* info on nulls */
							  &(heapTuple->t_self),		/* tid of heap tuple */
							  heapRelation);

		/* ----------------
		 *		keep track of index inserts for debugging
		 * ----------------
		 */
		IncrIndexInserted();

		/* ----------------
		 *		free index tuple after insertion
		 * ----------------
		 */
		if (result)
			pfree(result);
	}
	if (econtext != NULL)
		pfree(econtext);
}

void
SetChangedParamList(Plan *node, List *newchg)
{
	List	   *nl;

	foreach(nl, newchg)
	{
		int			paramId = lfirsti(nl);

		/* if this node doesn't depend on a param ... */
		if (!intMember(paramId, node->extParam) &&
			!intMember(paramId, node->locParam))
			continue;
		/* if this param is already in list of changed ones ... */
		if (intMember(paramId, node->chgParam))
			continue;
		/* else - add this param to the list */
		node->chgParam = lappendi(node->chgParam, paramId);
	}

}