Пример #1
0
/*
 * infer_tupledesc
 *
 * Given a stream, infer a TupleDesc based on the supertype of all
 * the casted types for each of the stream's columns
 */
static void
infer_tupledesc(StreamTargetsEntry *stream)
{
	HASH_SEQ_STATUS status;
	StreamColumnsEntry *entry;
	List *names = NIL;
	List *types = NIL;
	List *mods = NIL;
	List *collations = NIL;
	Const *preferred = makeConst(NUMERIC_OID, -1, 0, -1, 0, false, false);

	hash_seq_init(&status, stream->colstotypes);
	while ((entry = (StreamColumnsEntry *) hash_seq_search(&status)) != NULL)
	{
		char err[128];
		Oid supertype;
		char category;
		bool typispreferred;
		Oid t = exprType(linitial(entry->types));

		/*
		 * If there are any numeric types in our target types, we prepend a float8
		 * to the list of types to select from, as that is our preferred type when
		 * there is any ambiguity about how to interpret numeric types.
		 */
		get_type_category_preferred(t, &category, &typispreferred);
		if (category == TYPCATEGORY_NUMERIC)
			entry->types = lcons(preferred, entry->types);

		sprintf(err, "type conflict with stream \"%s\":", get_rel_name(stream->relid));
		supertype = select_common_type(NULL, entry->types, err, NULL);

		names = lappend(names, makeString(entry->name));
		types = lappend_int(types, supertype);
		mods = lappend_int(mods, -1);
		collations = lappend_int(collations, 0);
	}

	stream->desc = BuildDescFromLists(names, types, mods, collations);
}
Пример #2
0
/* ----------------------------------------------------------------
 *		ExecInitFunctionScan
 * ----------------------------------------------------------------
 */
FunctionScanState *
ExecInitFunctionScan(FunctionScan *node, EState *estate, int eflags)
{
	FunctionScanState *scanstate;
	RangeTblEntry *rte;
	Oid			funcrettype;
	TypeFuncClass functypclass;
	TupleDesc	tupdesc = NULL;

	/*
	 * FunctionScan should not have any children.
	 */
	Assert(outerPlan(node) == NULL);
	Assert(innerPlan(node) == NULL);

	/*
	 * create new ScanState for node
	 */
	scanstate = makeNode(FunctionScanState);
	scanstate->ss.ps.plan = (Plan *) node;
	scanstate->ss.ps.state = estate;

	/*
	 * Miscellaneous initialization
	 *
	 * create expression context for node
	 */
	ExecAssignExprContext(estate, &scanstate->ss.ps);

#define FUNCTIONSCAN_NSLOTS 2

	/*
	 * tuple table initialization
	 */
	ExecInitResultTupleSlot(estate, &scanstate->ss.ps);
	ExecInitScanTupleSlot(estate, &scanstate->ss);

	/*
	 * initialize child expressions
	 */
	scanstate->ss.ps.targetlist = (List *)
		ExecInitExpr((Expr *) node->scan.plan.targetlist,
					 (PlanState *) scanstate);
	scanstate->ss.ps.qual = (List *)
		ExecInitExpr((Expr *) node->scan.plan.qual,
					 (PlanState *) scanstate);

	/* Check if targetlist or qual contains a var node referencing the ctid column */
	scanstate->cdb_want_ctid = contain_ctid_var_reference(&node->scan);

    ItemPointerSet(&scanstate->cdb_fake_ctid, 0, 0);
    ItemPointerSet(&scanstate->cdb_mark_ctid, 0, 0);

	/*
	 * get info about function
	 */
	rte = rt_fetch(node->scan.scanrelid, estate->es_range_table);
	Assert(rte->rtekind == RTE_FUNCTION);

	/*
	 * Now determine if the function returns a simple or composite type, and
	 * build an appropriate tupdesc.
	 */
	functypclass = get_expr_result_type(rte->funcexpr,
										&funcrettype,
										&tupdesc);

	if (functypclass == TYPEFUNC_COMPOSITE)
	{
		/* Composite data type, e.g. a table's row type */
		Assert(tupdesc);
		/* Must copy it out of typcache for safety */
		tupdesc = CreateTupleDescCopy(tupdesc);
	}
	else if (functypclass == TYPEFUNC_SCALAR)
	{
		/* Base data type, i.e. scalar */
		char	   *attname = strVal(linitial(rte->eref->colnames));

		tupdesc = CreateTemplateTupleDesc(1, false);
		TupleDescInitEntry(tupdesc,
						   (AttrNumber) 1,
						   attname,
						   funcrettype,
						   -1,
						   0);
	}
	else if (functypclass == TYPEFUNC_RECORD)
	{
		tupdesc = BuildDescFromLists(rte->eref->colnames,
									 rte->funccoltypes,
									 rte->funccoltypmods);
	}
	else
	{
		/* crummy error message, but parser should have caught this */
		elog(ERROR, "function in FROM has unsupported return type");
	}

	/*
	 * For RECORD results, make sure a typmod has been assigned.  (The
	 * function should do this for itself, but let's cover things in case it
	 * doesn't.)
	 */
	BlessTupleDesc(tupdesc);

	scanstate->tupdesc = tupdesc;
	ExecAssignScanType(&scanstate->ss, tupdesc);

	/*
	 * Other node-specific setup
	 */
	scanstate->tuplestorestate = NULL;
	scanstate->funcexpr = ExecInitExpr((Expr *) rte->funcexpr,
									   (PlanState *) scanstate);

	/*
	 * Initialize result tuple type and projection info.
	 */
	ExecAssignResultTypeFromTL(&scanstate->ss.ps);
	ExecAssignScanProjectionInfo(&scanstate->ss);

	initGpmonPktForFunctionScan((Plan *)node, &scanstate->ss.ps.gpmon_pkt, estate);
	
	if (gp_resqueue_memory_policy != RESQUEUE_MEMORY_POLICY_NONE)
	{
		SPI_ReserveMemory(((Plan *)node)->operatorMemKB * 1024L);
	}

	return scanstate;
}
Пример #3
0
/* ----------------------------------------------------------------
 *		ExecInitFunctionScan
 * ----------------------------------------------------------------
 */
FunctionScanState *
ExecInitFunctionScan(FunctionScan *node, EState *estate, int eflags)
{
	FunctionScanState *scanstate;
	Oid			funcrettype;
	TypeFuncClass functypclass;
	TupleDesc	tupdesc = NULL;

	/* check for unsupported flags */
	Assert(!(eflags & EXEC_FLAG_MARK));

	/*
	 * FunctionScan should not have any children.
	 */
	Assert(outerPlan(node) == NULL);
	Assert(innerPlan(node) == NULL);

	/*
	 * create new ScanState for node
	 */
	scanstate = makeNode(FunctionScanState);
	scanstate->ss.ps.plan = (Plan *) node;
	scanstate->ss.ps.state = estate;
	scanstate->eflags = eflags;

	/*
	 * Miscellaneous initialization
	 *
	 * create expression context for node
	 */
	ExecAssignExprContext(estate, &scanstate->ss.ps);

	/*
	 * tuple table initialization
	 */
	ExecInitResultTupleSlot(estate, &scanstate->ss.ps);
	ExecInitScanTupleSlot(estate, &scanstate->ss);

	/*
	 * initialize child expressions
	 */
	scanstate->ss.ps.targetlist = (List *)
		ExecInitExpr((Expr *) node->scan.plan.targetlist,
					 (PlanState *) scanstate);
	scanstate->ss.ps.qual = (List *)
		ExecInitExpr((Expr *) node->scan.plan.qual,
					 (PlanState *) scanstate);

	/*
	 * Now determine if the function returns a simple or composite type, and
	 * build an appropriate tupdesc.
	 */
	functypclass = get_expr_result_type(node->funcexpr,
										&funcrettype,
										&tupdesc);

	if (functypclass == TYPEFUNC_COMPOSITE)
	{
		/* Composite data type, e.g. a table's row type */
		Assert(tupdesc);
		/* Must copy it out of typcache for safety */
		tupdesc = CreateTupleDescCopy(tupdesc);
	}
	else if (functypclass == TYPEFUNC_SCALAR)
	{
		/* Base data type, i.e. scalar */
		char	   *attname = strVal(linitial(node->funccolnames));

		tupdesc = CreateTemplateTupleDesc(1, false);
		TupleDescInitEntry(tupdesc,
						   (AttrNumber) 1,
						   attname,
						   funcrettype,
						   -1,
						   0);
	}
	else if (functypclass == TYPEFUNC_RECORD)
	{
		tupdesc = BuildDescFromLists(node->funccolnames,
									 node->funccoltypes,
									 node->funccoltypmods);
	}
	else
	{
		/* crummy error message, but parser should have caught this */
		elog(ERROR, "function in FROM has unsupported return type");
	}

	/*
	 * For RECORD results, make sure a typmod has been assigned.  (The
	 * function should do this for itself, but let's cover things in case it
	 * doesn't.)
	 */
	BlessTupleDesc(tupdesc);

	scanstate->tupdesc = tupdesc;
	ExecAssignScanType(&scanstate->ss, tupdesc);

	/*
	 * Other node-specific setup
	 */
	scanstate->tuplestorestate = NULL;
	scanstate->funcexpr = ExecInitExpr((Expr *) node->funcexpr,
									   (PlanState *) scanstate);

	scanstate->ss.ps.ps_TupFromTlist = false;

	/*
	 * Initialize result tuple type and projection info.
	 */
	ExecAssignResultTypeFromTL(&scanstate->ss.ps);
	ExecAssignScanProjectionInfo(&scanstate->ss);

	return scanstate;
}