/*
* 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);
}
/* ----------------------------------------------------------------
* 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;
}
/* ----------------------------------------------------------------
* 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;
}
