void
initGpmonPktForTableScan(Plan *planNode, gpmon_packet_t *gpmon_pkt, EState *estate)
{
Assert(planNode != NULL && gpmon_pkt != NULL);
Assert(IsA(planNode, TableScan) ||
IsA(planNode, SeqScan) ||
IsA(planNode, AppendOnlyScan) ||
IsA(planNode, AOCSScan));
RangeTblEntry *rte = rt_fetch(((Scan *)planNode)->scanrelid, estate->es_range_table);
char schema_rel_name[SCAN_REL_NAME_BUF_SIZE] = {0};
Assert(GPMON_TABLESCAN_TOTAL <= (int)GPMON_QEXEC_M_COUNT);
InitPlanNodeGpmonPkt(planNode, gpmon_pkt, estate, PMNT_TableScan,
(int64) planNode->plan_rows, GetScanRelNameGpmon(rte->relid, schema_rel_name));
}
void
initGpmonPktForExternalScan(Plan *planNode, gpmon_packet_t *gpmon_pkt, EState *estate)
{
Assert(planNode != NULL && gpmon_pkt != NULL && IsA(planNode, ExternalScan));
{
RangeTblEntry *rte = rt_fetch(((ExternalScan *)planNode)->scan.scanrelid,
estate->es_range_table);
char schema_rel_name[SCAN_REL_NAME_BUF_SIZE] = {0};
Assert(GPMON_EXTSCAN_TOTAL <= (int)GPMON_QEXEC_M_COUNT);
InitPlanNodeGpmonPkt(planNode, gpmon_pkt, estate, PMNT_ExternalScan,
(int64)planNode->plan_rows,
GetScanRelNameGpmon(rte->relid, schema_rel_name));
}
}
/**
* This method looks at the Append part of the plan under a join and extracts out interesting bits of information.
* These include: partitionOid of the master table, partitionInfo that is a struct containing partitioning information,
* what are the partitioning keys and what does an all null row of the partitioned table look like.
*/
static void MatchAppendPattern(Plan *append, PartitionJoinMutatorContext *ctx)
{
ctx->partitionOid = InvalidOid;
/**
* It is possible we have already applied the transformation to this subtree.
* Check for result node as child.
*/
Append *appendNode = (Append *) append;
Assert(list_length(appendNode->appendplans) > 0);
Plan *child = (Plan *) list_nth(appendNode->appendplans, 0);
if (IsA(child, Result))
{
ctx->safeToConvert = false;
return;
}
/**
* Find all the vars in the targetlist and check if they're from a partitioned table.
*/
List *allVars = extract_nodes(NULL /* PlannerGlobal */, (Node *) append->targetlist, T_Var);
ListCell *lc = NULL;
foreach (lc, allVars)
{
Var *v = (Var *) lfirst(lc);
RangeTblEntry *rte = rt_fetch(v->varno, ctx->rtable);
Assert(rte);
if (!rel_is_partitioned(rte->relid))
{
ctx->safeToConvert = false;
return;
}
if (ctx->partitionOid == InvalidOid)
{
ctx->partitionOid = rte->relid;
ctx->partitionVarno = v->varno;
}
if (ctx->partitionOid != rte->relid)
{
ctx->safeToConvert = false;
return;
}
}
/*
* plan_set_operations
*
* Plans the queries for a tree of set operations (UNION/INTERSECT/EXCEPT)
*
* This routine only deals with the setOperations tree of the given query.
* Any top-level ORDER BY requested in root->parse->sortClause will be added
* when we return to grouping_planner.
*
* tuple_fraction is the fraction of tuples we expect will be retrieved.
* tuple_fraction is interpreted as for grouping_planner(); in particular,
* zero means "all the tuples will be fetched". Any LIMIT present at the
* top level has already been factored into tuple_fraction.
*
* *sortClauses is an output argument: it is set to a list of SortClauses
* representing the result ordering of the topmost set operation.
*/
Plan *
plan_set_operations(PlannerInfo *root, double tuple_fraction,
List **sortClauses)
{
Query *parse = root->parse;
SetOperationStmt *topop = (SetOperationStmt *) parse->setOperations;
Node *node;
Query *leftmostQuery;
Assert(topop && IsA(topop, SetOperationStmt));
/* check for unsupported stuff */
Assert(parse->utilityStmt == NULL);
Assert(parse->jointree->fromlist == NIL);
Assert(parse->jointree->quals == NULL);
Assert(parse->groupClause == NIL);
Assert(parse->havingQual == NULL);
Assert(parse->distinctClause == NIL);
/*
* Find the leftmost component Query. We need to use its column names for
* all generated tlists (else SELECT INTO won't work right).
*/
node = topop->larg;
while (node && IsA(node, SetOperationStmt))
node = ((SetOperationStmt *) node)->larg;
Assert(node && IsA(node, RangeTblRef));
leftmostQuery = rt_fetch(((RangeTblRef *) node)->rtindex,
parse->rtable)->subquery;
Assert(leftmostQuery != NULL);
/*
* Recurse on setOperations tree to generate plans for set ops. The final
* output plan should have just the column types shown as the output from
* the top-level node, plus possibly resjunk working columns (we can rely
* on upper-level nodes to deal with that).
*/
return recurse_set_operations((Node *) topop, root, tuple_fraction,
topop->colTypes, true, -1,
leftmostQuery->targetList,
sortClauses);
}
/*
* optimize_minmax_aggregates - check for optimizing MIN/MAX via indexes
*
* This checks to see if we can replace MIN/MAX aggregate functions by
* subqueries of the form
* (SELECT col FROM tab WHERE ... ORDER BY col ASC/DESC LIMIT 1)
* Given a suitable index on tab.col, this can be much faster than the
* generic scan-all-the-rows plan.
*
* We are passed the preprocessed tlist, and the best path
* devised for computing the input of a standard Agg node. If we are able
* to optimize all the aggregates, and the result is estimated to be cheaper
* than the generic aggregate method, then generate and return a Plan that
* does it that way. Otherwise, return NULL.
*/
Plan *
optimize_minmax_aggregates(PlannerInfo *root, List *tlist, Path *best_path)
{
Query *parse = root->parse;
FromExpr *jtnode;
RangeTblRef *rtr;
RangeTblEntry *rte;
RelOptInfo *rel;
List *aggs_list;
ListCell *l;
Cost total_cost;
Path agg_p;
Plan *plan;
Node *hqual;
QualCost tlist_cost;
/* Nothing to do if query has no aggregates */
if (!parse->hasAggs)
return NULL;
Assert(!parse->setOperations); /* shouldn't get here if a setop */
Assert(parse->rowMarks == NIL); /* nor if FOR UPDATE */
/*
* Reject unoptimizable cases.
*
* We don't handle GROUP BY, because our current implementations of
* grouping require looking at all the rows anyway, and so there's not
* much point in optimizing MIN/MAX.
*/
if (parse->groupClause)
return NULL;
/*
* We also restrict the query to reference exactly one table, since join
* conditions can't be handled reasonably. (We could perhaps handle a
* query containing cartesian-product joins, but it hardly seems worth the
* trouble.) However, the single real table could be buried in several
* levels of FromExpr.
*/
jtnode = parse->jointree;
while (IsA(jtnode, FromExpr))
{
if (list_length(jtnode->fromlist) != 1)
return NULL;
jtnode = linitial(jtnode->fromlist);
}
if (!IsA(jtnode, RangeTblRef))
return NULL;
rtr = (RangeTblRef *) jtnode;
rte = rt_fetch(rtr->rtindex, parse->rtable);
if (rte->rtekind != RTE_RELATION || rte->inh)
return NULL;
rel = find_base_rel(root, rtr->rtindex);
/*
* Since this optimization is not applicable all that often, we want to
* fall out before doing very much work if possible. Therefore we do the
* work in several passes. The first pass scans the tlist and HAVING qual
* to find all the aggregates and verify that each of them is a MIN/MAX
* aggregate. If that succeeds, the second pass looks at each aggregate
* to see if it is optimizable; if so we make an IndexPath describing how
* we would scan it. (We do not try to optimize if only some aggs are
* optimizable, since that means we'll have to scan all the rows anyway.)
* If that succeeds, we have enough info to compare costs against the
* generic implementation. Only if that test passes do we build a Plan.
*/
/* Pass 1: find all the aggregates */
aggs_list = NIL;
if (find_minmax_aggs_walker((Node *) tlist, &aggs_list))
return NULL;
if (find_minmax_aggs_walker(parse->havingQual, &aggs_list))
return NULL;
/* Pass 2: see if each one is optimizable */
total_cost = 0;
foreach(l, aggs_list)
{
MinMaxAggInfo *info = (MinMaxAggInfo *) lfirst(l);
if (!build_minmax_path(root, rel, info))
return NULL;
total_cost += info->pathcost;
}
/* ----------------------------------------------------------------
* ExecInitSubqueryScan
* ----------------------------------------------------------------
*/
SubqueryScanState *
ExecInitSubqueryScan(SubqueryScan *node, EState *estate)
{
SubqueryScanState *subquerystate;
RangeTblEntry *rte;
EState *sp_estate;
MemoryContext oldcontext;
/*
* SubqueryScan should not have any "normal" children.
*/
Assert(outerPlan(node) == NULL);
Assert(innerPlan(node) == NULL);
/*
* create state structure
*/
subquerystate = makeNode(SubqueryScanState);
subquerystate->ss.ps.plan = (Plan *) node;
subquerystate->ss.ps.state = estate;
/*
* Miscellaneous initialization
*
* create expression context for node
*/
ExecAssignExprContext(estate, &subquerystate->ss.ps);
/*
* initialize child expressions
*/
subquerystate->ss.ps.targetlist = (List *)
ExecInitExpr((Expr *) node->scan.plan.targetlist,
(PlanState *) subquerystate);
subquerystate->ss.ps.qual = (List *)
ExecInitExpr((Expr *) node->scan.plan.qual,
(PlanState *) subquerystate);
#define SUBQUERYSCAN_NSLOTS 2
/*
* tuple table initialization
*/
ExecInitResultTupleSlot(estate, &subquerystate->ss.ps);
ExecInitScanTupleSlot(estate, &subquerystate->ss);
/*
* initialize subquery
*
* This should agree with ExecInitSubPlan
*/
rte = rt_fetch(node->scan.scanrelid, estate->es_range_table);
Assert(rte->rtekind == RTE_SUBQUERY);
/*
* Do access checking on the rangetable entries in the subquery.
*/
ExecCheckRTPerms(rte->subquery->rtable);
/*
* The subquery needs its own EState because it has its own rangetable. It
* shares our Param ID space, however. XXX if rangetable access were done
* differently, the subquery could share our EState, which would eliminate
* some thrashing about in this module...
*/
sp_estate = CreateExecutorState();
subquerystate->sss_SubEState = sp_estate;
oldcontext = MemoryContextSwitchTo(sp_estate->es_query_cxt);
sp_estate->es_range_table = rte->subquery->rtable;
sp_estate->es_param_list_info = estate->es_param_list_info;
sp_estate->es_param_exec_vals = estate->es_param_exec_vals;
sp_estate->es_tupleTable =
ExecCreateTupleTable(ExecCountSlotsNode(node->subplan) + 10);
sp_estate->es_snapshot = estate->es_snapshot;
sp_estate->es_crosscheck_snapshot = estate->es_crosscheck_snapshot;
sp_estate->es_instrument = estate->es_instrument;
/*
* Start up the subplan (this is a very cut-down form of InitPlan())
*/
subquerystate->subplan = ExecInitNode(node->subplan, sp_estate);
MemoryContextSwitchTo(oldcontext);
subquerystate->ss.ps.ps_TupFromTlist = false;
/*
* Initialize scan tuple type (needed by ExecAssignScanProjectionInfo)
*/
ExecAssignScanType(&subquerystate->ss,
ExecGetResultType(subquerystate->subplan),
false);
/*
* Initialize result tuple type and projection info.
*/
ExecAssignResultTypeFromTL(&subquerystate->ss.ps);
ExecAssignScanProjectionInfo(&subquerystate->ss);
return subquerystate;
}
/* ----------------------------------------------------------------
* 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;
}
/*
* Handle CTIDs of views.
* CTID should be defined in the view and it must
* correspond to the CTID of a base relation.
*/
static Datum
currtid_for_view(Relation viewrel, ItemPointer tid)
{
TupleDesc att = RelationGetDescr(viewrel);
RuleLock *rulelock;
RewriteRule *rewrite;
int i,
natts = att->natts,
tididx = -1;
for (i = 0; i < natts; i++)
{
Form_pg_attribute attr = TupleDescAttr(att, i);
if (strcmp(NameStr(attr->attname), "ctid") == 0)
{
if (attr->atttypid != TIDOID)
elog(ERROR, "ctid isn't of type TID");
tididx = i;
break;
}
}
if (tididx < 0)
elog(ERROR, "currtid cannot handle views with no CTID");
rulelock = viewrel->rd_rules;
if (!rulelock)
elog(ERROR, "the view has no rules");
for (i = 0; i < rulelock->numLocks; i++)
{
rewrite = rulelock->rules[i];
if (rewrite->event == CMD_SELECT)
{
Query *query;
TargetEntry *tle;
if (list_length(rewrite->actions) != 1)
elog(ERROR, "only one select rule is allowed in views");
query = (Query *) linitial(rewrite->actions);
tle = get_tle_by_resno(query->targetList, tididx + 1);
if (tle && tle->expr && IsA(tle->expr, Var))
{
Var *var = (Var *) tle->expr;
RangeTblEntry *rte;
if (!IS_SPECIAL_VARNO(var->varno) &&
var->varattno == SelfItemPointerAttributeNumber)
{
rte = rt_fetch(var->varno, query->rtable);
if (rte)
{
heap_close(viewrel, AccessShareLock);
return DirectFunctionCall2(currtid_byreloid, ObjectIdGetDatum(rte->relid), PointerGetDatum(tid));
}
}
}
break;
}
}
elog(ERROR, "currtid cannot handle this view");
return (Datum) 0;
}
/*
* recurse_set_operations
* Recursively handle one step in a tree of set operations
*
* colTypes: list of type OIDs of expected output columns
* junkOK: if true, child resjunk columns may be left in the result
* flag: if >= 0, add a resjunk output column indicating value of flag
* refnames_tlist: targetlist to take column names from
*/
static Plan *
recurse_set_operations(Node *setOp, Query *parse,
List *colTypes, bool junkOK,
int flag, List *refnames_tlist)
{
if (IsA(setOp, RangeTblRef))
{
RangeTblRef *rtr = (RangeTblRef *) setOp;
RangeTblEntry *rte = rt_fetch(rtr->rtindex, parse->rtable);
Query *subquery = rte->subquery;
Plan *subplan,
*plan;
Assert(subquery != NULL);
/*
* Generate plan for primitive subquery
*/
subplan = subquery_planner(subquery, 0.0 /* default case */ );
/*
* Add a SubqueryScan with the caller-requested targetlist
*/
plan = (Plan *)
make_subqueryscan(generate_setop_tlist(colTypes, flag, true,
subplan->targetlist,
refnames_tlist),
NIL,
rtr->rtindex,
subplan);
return plan;
}
else if (IsA(setOp, SetOperationStmt))
{
SetOperationStmt *op = (SetOperationStmt *) setOp;
Plan *plan;
/* UNIONs are much different from INTERSECT/EXCEPT */
if (op->op == SETOP_UNION)
plan = generate_union_plan(op, parse, refnames_tlist);
else
plan = generate_nonunion_plan(op, parse, refnames_tlist);
/*
* If necessary, add a Result node to project the caller-requested
* output columns.
*
* XXX you don't really want to know about this: setrefs.c will apply
* replace_vars_with_subplan_refs() to the Result node's tlist.
* This would fail if the Vars generated by generate_setop_tlist()
* were not exactly equal() to the corresponding tlist entries of
* the subplan. However, since the subplan was generated by
* generate_union_plan() or generate_nonunion_plan(), and hence
* its tlist was generated by generate_append_tlist(), this will
* work.
*/
if (flag >= 0 ||
!tlist_same_datatypes(plan->targetlist, colTypes, junkOK))
{
plan = (Plan *)
make_result(generate_setop_tlist(colTypes, flag, false,
plan->targetlist,
refnames_tlist),
NULL,
plan);
}
return plan;
}
else
{
elog(ERROR, "unrecognized node type: %d",
(int) nodeTag(setOp));
return NULL; /* keep compiler quiet */
}
}
/* ----------------------------------------------------------------
* ExecInitBitmapHeapScan
*
* Initializes the scan's state information.
* ----------------------------------------------------------------
*/
BitmapHeapScanState *
ExecInitBitmapHeapScan(BitmapHeapScan *node, EState *estate, int eflags)
{
BitmapHeapScanState *scanstate;
RangeTblEntry *rtentry;
Index relid;
Oid reloid;
Relation currentRelation;
/* check for unsupported flags */
Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK)));
/*
* create state structure
*/
scanstate = makeNode(BitmapHeapScanState);
scanstate->ss.ps.plan = (Plan *) node;
scanstate->ss.ps.state = estate;
scanstate->tbm = NULL;
scanstate->tbmres = NULL;
/*
* Miscellaneous initialization
*
* create expression context for node
*/
ExecAssignExprContext(estate, &scanstate->ss.ps);
/*
* 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);
scanstate->bitmapqualorig = (List *)
ExecInitExpr((Expr *) node->bitmapqualorig,
(PlanState *) scanstate);
#define BITMAPHEAPSCAN_NSLOTS 2
/*
* tuple table initialization
*/
ExecInitResultTupleSlot(estate, &scanstate->ss.ps);
ExecInitScanTupleSlot(estate, &scanstate->ss);
CXT1_printf("ExecInitBitmapHeapScan: context is %d\n", CurrentMemoryContext);
/*
* open the base relation and acquire AccessShareLock on it.
*/
relid = node->scan.scanrelid;
rtentry = rt_fetch(relid, estate->es_range_table);
reloid = rtentry->relid;
currentRelation = heap_open(reloid, AccessShareLock);
scanstate->ss.ss_currentRelation = currentRelation;
/*
* Even though we aren't going to do a conventional seqscan, it is useful
* to create a HeapScanDesc --- this checks the relation size and sets up
* statistical infrastructure for us.
*/
scanstate->ss.ss_currentScanDesc = heap_beginscan(currentRelation,
estate->es_snapshot,
0,
NULL);
/*
* One problem is that heap_beginscan counts a "sequential scan" start,
* when we actually aren't doing any such thing. Reverse out the added
* scan count. (Eventually we may want to count bitmap scans separately.)
*/
pgstat_discount_heap_scan(&scanstate->ss.ss_currentScanDesc->rs_pgstat_info);
/*
* get the scan type from the relation descriptor.
*/
ExecAssignScanType(&scanstate->ss, RelationGetDescr(currentRelation), false);
/*
* Initialize result tuple type and projection info.
*/
ExecAssignResultTypeFromTL(&scanstate->ss.ps);
ExecAssignScanProjectionInfo(&scanstate->ss);
/*
* initialize child nodes
*
* We do this last because the child nodes will open indexscans on our
* relation's indexes, and we want to be sure we have acquired a lock
* on the relation first.
*/
outerPlanState(scanstate) = ExecInitNode(outerPlan(node), estate, eflags);
if (IsA(outerPlan(node), BitmapIndexScan))
node->inmem =
(((BitmapIndexScan*)outerPlan(node))->indexam !=
BITMAP_AM_OID);
else if (IsA(outerPlan(node), BitmapAnd))
node->inmem = ((BitmapAnd*)outerPlan(node))->inmem;
else if (IsA(outerPlan(node), BitmapOr))
node->inmem = ((BitmapOr*)outerPlan(node))->inmem;
else
node->inmem = true;
/*
* all done.
*/
return scanstate;
}
/*
* recurse_set_operations
* Recursively handle one step in a tree of set operations
*
* tuple_fraction: fraction of tuples we expect to retrieve from node
* colTypes: list of type OIDs of expected output columns
* junkOK: if true, child resjunk columns may be left in the result
* flag: if >= 0, add a resjunk output column indicating value of flag
* refnames_tlist: targetlist to take column names from
* *sortClauses: receives list of SortClauses for result plan, if any
*
* We don't have to care about typmods here: the only allowed difference
* between set-op input and output typmods is input is a specific typmod
* and output is -1, and that does not require a coercion.
*/
static Plan *
recurse_set_operations(Node *setOp, PlannerInfo *root,
double tuple_fraction,
List *colTypes, bool junkOK,
int flag, List *refnames_tlist,
List **sortClauses)
{
if (IsA(setOp, RangeTblRef))
{
RangeTblRef *rtr = (RangeTblRef *) setOp;
RangeTblEntry *rte = rt_fetch(rtr->rtindex, root->parse->rtable);
Query *subquery = rte->subquery;
Plan *subplan,
*plan;
Assert(subquery != NULL);
/*
* Generate plan for primitive subquery
*/
subplan = subquery_planner(subquery, tuple_fraction, NULL);
/*
* Add a SubqueryScan with the caller-requested targetlist
*/
plan = (Plan *)
make_subqueryscan(generate_setop_tlist(colTypes, flag,
rtr->rtindex,
true,
subplan->targetlist,
refnames_tlist),
NIL,
rtr->rtindex,
subplan);
/*
* We don't bother to determine the subquery's output ordering since
* it won't be reflected in the set-op result anyhow.
*/
*sortClauses = NIL;
return plan;
}
else if (IsA(setOp, SetOperationStmt))
{
SetOperationStmt *op = (SetOperationStmt *) setOp;
Plan *plan;
/* UNIONs are much different from INTERSECT/EXCEPT */
if (op->op == SETOP_UNION)
plan = generate_union_plan(op, root, tuple_fraction,
refnames_tlist,
sortClauses);
else
plan = generate_nonunion_plan(op, root,
refnames_tlist,
sortClauses);
/*
* If necessary, add a Result node to project the caller-requested
* output columns.
*
* XXX you don't really want to know about this: setrefs.c will apply
* replace_vars_with_subplan_refs() to the Result node's tlist. This
* would fail if the Vars generated by generate_setop_tlist() were not
* exactly equal() to the corresponding tlist entries of the subplan.
* However, since the subplan was generated by generate_union_plan()
* or generate_nonunion_plan(), and hence its tlist was generated by
* generate_append_tlist(), this will work. We just tell
* generate_setop_tlist() to use varno 0.
*/
if (flag >= 0 ||
!tlist_same_datatypes(plan->targetlist, colTypes, junkOK))
{
plan = (Plan *)
make_result(generate_setop_tlist(colTypes, flag,
0,
false,
plan->targetlist,
refnames_tlist),
NULL,
plan);
}
return plan;
}
else
{
elog(ERROR, "unrecognized node type: %d",
(int) nodeTag(setOp));
return NULL; /* keep compiler quiet */
}
}
/* ----------------------------------------------------------------
* ExecInitFunctionScan
* ----------------------------------------------------------------
*/
FunctionScanState *
ExecInitFunctionScan(FunctionScan *node, EState *estate)
{
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);
/*
* get info about function
*/
rte = rt_fetch(node->scan.scanrelid, estate->es_range_table);
Assert(rte->rtekind == RTE_FUNCTION);
funcrettype = exprType(rte->funcexpr);
/*
* Now determine if the function returns a simple or composite type,
* and build an appropriate tupdesc.
*/
functypclass = get_type_func_class(funcrettype);
if (functypclass == TYPEFUNC_COMPOSITE)
{
/* Composite data type, e.g. a table's row type */
tupdesc = CreateTupleDescCopy(lookup_rowtype_tupdesc(funcrettype, -1));
}
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 = BuildDescForRelation(rte->coldeflist);
}
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.)
*/
if (tupdesc->tdtypeid == RECORDOID && tupdesc->tdtypmod < 0)
assign_record_type_typmod(tupdesc);
scanstate->tupdesc = tupdesc;
ExecSetSlotDescriptor(scanstate->ss.ss_ScanTupleSlot,
tupdesc, false);
/*
* Other node-specific setup
*/
scanstate->tuplestorestate = NULL;
scanstate->funcexpr = ExecInitExpr((Expr *) rte->funcexpr,
(PlanState *) scanstate);
scanstate->ss.ps.ps_TupFromTlist = false;
/*
* Initialize result tuple type and projection info.
*/
ExecAssignResultTypeFromTL(&scanstate->ss.ps);
ExecAssignProjectionInfo(&scanstate->ss.ps);
return scanstate;
}
