Header And Logo
|
#include "postgres.h"#include "access/htup_details.h"#include "catalog/pg_operator.h"#include "catalog/pg_type.h"#include "executor/executor.h"#include "miscadmin.h"#include "nodes/makefuncs.h"#include "nodes/nodeFuncs.h"#include "optimizer/clauses.h"#include "optimizer/cost.h"#include "optimizer/planmain.h"#include "optimizer/planner.h"#include "optimizer/prep.h"#include "optimizer/subselect.h"#include "optimizer/var.h"#include "parser/parse_relation.h"#include "rewrite/rewriteManip.h"#include "utils/builtins.h"#include "utils/lsyscache.h"#include "utils/syscache.h"
Go to the source code of this file.
| typedef struct convert_testexpr_context convert_testexpr_context |
| typedef struct finalize_primnode_context finalize_primnode_context |
| typedef struct process_sublinks_context process_sublinks_context |
| Param* assign_nestloop_param_placeholdervar | ( | PlannerInfo * | root, | |
| PlaceHolderVar * | phv | |||
| ) |
Definition at line 275 of file subselect.c.
References Assert, assign_param_for_placeholdervar(), exprCollation(), exprType(), exprTypmod(), i, Param::location, makeNode, Param::paramcollid, Param::paramid, Param::paramkind, Param::paramtype, Param::paramtypmod, PlaceHolderVar::phexpr, and PlaceHolderVar::phlevelsup.
Referenced by replace_nestloop_params_mutator().
{
Param *retval;
int i;
Assert(phv->phlevelsup == 0);
i = assign_param_for_placeholdervar(root, phv);
retval = makeNode(Param);
retval->paramkind = PARAM_EXEC;
retval->paramid = i;
retval->paramtype = exprType((Node *) phv->phexpr);
retval->paramtypmod = exprTypmod((Node *) phv->phexpr);
retval->paramcollid = exprCollation((Node *) phv->phexpr);
retval->location = -1;
return retval;
}
| Param* assign_nestloop_param_var | ( | PlannerInfo * | root, | |
| Var * | var | |||
| ) |
Definition at line 171 of file subselect.c.
References Assert, assign_param_for_var(), i, Var::location, Param::location, makeNode, Param::paramcollid, Param::paramid, Param::paramkind, Param::paramtype, Param::paramtypmod, Var::varcollid, Var::varlevelsup, Var::vartype, and Var::vartypmod.
Referenced by replace_nestloop_params_mutator().
{
Param *retval;
int i;
Assert(var->varlevelsup == 0);
i = assign_param_for_var(root, var);
retval = makeNode(Param);
retval->paramkind = PARAM_EXEC;
retval->paramid = i;
retval->paramtype = var->vartype;
retval->paramtypmod = var->vartypmod;
retval->paramcollid = var->varcollid;
retval->location = var->location;
return retval;
}
| static int assign_param_for_placeholdervar | ( | PlannerInfo * | root, | |
| PlaceHolderVar * | phv | |||
| ) | [static] |
Definition at line 199 of file subselect.c.
References Assert, copyObject(), PlannerInfo::glob, IncrementVarSublevelsUp(), IsA, PlannerParamItem::item, lappend(), lfirst, makeNode, PlannerGlobal::nParamExec, PlannerParamItem::paramId, PlannerInfo::parent_root, PlaceHolderVar::phid, PlaceHolderVar::phlevelsup, and PlannerInfo::plan_params.
Referenced by assign_nestloop_param_placeholdervar(), and replace_outer_placeholdervar().
{
ListCell *ppl;
PlannerParamItem *pitem;
Index levelsup;
/* Find the query level the PHV belongs to */
for (levelsup = phv->phlevelsup; levelsup > 0; levelsup--)
root = root->parent_root;
/* If there's already a matching PlannerParamItem there, just use it */
foreach(ppl, root->plan_params)
{
pitem = (PlannerParamItem *) lfirst(ppl);
if (IsA(pitem->item, PlaceHolderVar))
{
PlaceHolderVar *pphv = (PlaceHolderVar *) pitem->item;
/* We assume comparing the PHIDs is sufficient */
if (pphv->phid == phv->phid)
return pitem->paramId;
}
}
/* Nope, so make a new one */
phv = (PlaceHolderVar *) copyObject(phv);
if (phv->phlevelsup != 0)
{
IncrementVarSublevelsUp((Node *) phv, -((int) phv->phlevelsup), 0);
Assert(phv->phlevelsup == 0);
}
pitem = makeNode(PlannerParamItem);
pitem->item = (Node *) phv;
pitem->paramId = root->glob->nParamExec++;
root->plan_params = lappend(root->plan_params, pitem);
return pitem->paramId;
}
| static int assign_param_for_var | ( | PlannerInfo * | root, | |
| Var * | var | |||
| ) | [static] |
Definition at line 91 of file subselect.c.
References copyObject(), PlannerInfo::glob, IsA, PlannerParamItem::item, lappend(), lfirst, makeNode, PlannerGlobal::nParamExec, PlannerParamItem::paramId, PlannerInfo::parent_root, PlannerInfo::plan_params, Var::varattno, Var::varcollid, Var::varlevelsup, Var::varno, Var::varnoold, Var::varoattno, Var::vartype, and Var::vartypmod.
Referenced by assign_nestloop_param_var(), and replace_outer_var().
{
ListCell *ppl;
PlannerParamItem *pitem;
Index levelsup;
/* Find the query level the Var belongs to */
for (levelsup = var->varlevelsup; levelsup > 0; levelsup--)
root = root->parent_root;
/* If there's already a matching PlannerParamItem there, just use it */
foreach(ppl, root->plan_params)
{
pitem = (PlannerParamItem *) lfirst(ppl);
if (IsA(pitem->item, Var))
{
Var *pvar = (Var *) pitem->item;
/*
* This comparison must match _equalVar(), except for ignoring
* varlevelsup. Note that _equalVar() ignores the location.
*/
if (pvar->varno == var->varno &&
pvar->varattno == var->varattno &&
pvar->vartype == var->vartype &&
pvar->vartypmod == var->vartypmod &&
pvar->varcollid == var->varcollid &&
pvar->varnoold == var->varnoold &&
pvar->varoattno == var->varoattno)
return pitem->paramId;
}
}
/* Nope, so make a new one */
var = (Var *) copyObject(var);
var->varlevelsup = 0;
pitem = makeNode(PlannerParamItem);
pitem->item = (Node *) var;
pitem->paramId = root->glob->nParamExec++;
root->plan_params = lappend(root->plan_params, pitem);
return pitem->paramId;
}
| static Node * build_subplan | ( | PlannerInfo * | root, | |
| Plan * | plan, | |||
| PlannerInfo * | subroot, | |||
| List * | plan_params, | |||
| SubLinkType | subLinkType, | |||
| Node * | testexpr, | |||
| bool | adjust_testexpr, | |||
| bool | unknownEqFalse | |||
| ) | [static] |
Definition at line 566 of file subselect.c.
References ANY_SUBLINK, arg, SubPlan::args, ARRAY_SUBLINK, Assert, bms_add_member(), BOOLOID, convert_testexpr(), cost_subplan(), elog, enable_material, ERROR, ExecMaterializesOutput(), EXISTS_SUBLINK, TargetEntry::expr, EXPR_SUBLINK, exprCollation(), exprType(), exprTypmod(), SubPlan::firstColCollation, SubPlan::firstColType, SubPlan::firstColTypmod, format_type_be(), generate_new_param(), generate_subquery_params(), get_array_type(), get_first_col_type(), PlannerInfo::glob, PlannerInfo::init_plans, InvalidOid, IsA, PlannerParamItem::item, lappend(), lappend_int(), lfirst, lfirst_int, linitial, list_copy(), list_length(), list_make1_int, lnext, makeNode, materialize_finished_plan(), NIL, nodeTag, NULL, OidIsValid, palloc(), Param::paramid, PlannerParamItem::paramId, SubPlan::paramIds, SubPlan::parParam, SubPlan::plan_id, SubPlan::plan_name, TargetEntry::resjunk, PlannerGlobal::rewindPlanIDs, ROWCOMPARE_SUBLINK, SubPlan::setParam, splan, SS_process_sublinks(), SubPlan::subLinkType, subplan_is_hashable(), PlannerGlobal::subplans, PlannerGlobal::subroots, Plan::targetlist, SubPlan::testexpr, testexpr_is_hashable(), SubPlan::unknownEqFalse, and SubPlan::useHashTable.
Referenced by make_subplan().
{
Node *result;
SubPlan *splan;
bool isInitPlan;
ListCell *lc;
/*
* Initialize the SubPlan node. Note plan_id, plan_name, and cost fields
* are set further down.
*/
splan = makeNode(SubPlan);
splan->subLinkType = subLinkType;
splan->testexpr = NULL;
splan->paramIds = NIL;
get_first_col_type(plan, &splan->firstColType, &splan->firstColTypmod,
&splan->firstColCollation);
splan->useHashTable = false;
splan->unknownEqFalse = unknownEqFalse;
splan->setParam = NIL;
splan->parParam = NIL;
splan->args = NIL;
/*
* Make parParam and args lists of param IDs and expressions that current
* query level will pass to this child plan.
*/
foreach(lc, plan_params)
{
PlannerParamItem *pitem = (PlannerParamItem *) lfirst(lc);
Node *arg = pitem->item;
/*
* The Var, PlaceHolderVar, or Aggref has already been adjusted to
* have the correct varlevelsup, phlevelsup, or agglevelsup.
*
* If it's a PlaceHolderVar or Aggref, its arguments might contain
* SubLinks, which have not yet been processed (see the comments for
* SS_replace_correlation_vars). Do that now.
*/
if (IsA(arg, PlaceHolderVar) ||
IsA(arg, Aggref))
arg = SS_process_sublinks(root, arg, false);
splan->parParam = lappend_int(splan->parParam, pitem->paramId);
splan->args = lappend(splan->args, arg);
}
/*
* Un-correlated or undirect correlated plans of EXISTS, EXPR, ARRAY, or
* ROWCOMPARE types can be used as initPlans. For EXISTS, EXPR, or ARRAY,
* we just produce a Param referring to the result of evaluating the
* initPlan. For ROWCOMPARE, we must modify the testexpr tree to contain
* PARAM_EXEC Params instead of the PARAM_SUBLINK Params emitted by the
* parser.
*/
if (splan->parParam == NIL && subLinkType == EXISTS_SUBLINK)
{
Param *prm;
Assert(testexpr == NULL);
prm = generate_new_param(root, BOOLOID, -1, InvalidOid);
splan->setParam = list_make1_int(prm->paramid);
isInitPlan = true;
result = (Node *) prm;
}
else if (splan->parParam == NIL && subLinkType == EXPR_SUBLINK)
{
TargetEntry *te = linitial(plan->targetlist);
Param *prm;
Assert(!te->resjunk);
Assert(testexpr == NULL);
prm = generate_new_param(root,
exprType((Node *) te->expr),
exprTypmod((Node *) te->expr),
exprCollation((Node *) te->expr));
splan->setParam = list_make1_int(prm->paramid);
isInitPlan = true;
result = (Node *) prm;
}
else if (splan->parParam == NIL && subLinkType == ARRAY_SUBLINK)
{
TargetEntry *te = linitial(plan->targetlist);
Oid arraytype;
Param *prm;
Assert(!te->resjunk);
Assert(testexpr == NULL);
arraytype = get_array_type(exprType((Node *) te->expr));
if (!OidIsValid(arraytype))
elog(ERROR, "could not find array type for datatype %s",
format_type_be(exprType((Node *) te->expr)));
prm = generate_new_param(root,
arraytype,
exprTypmod((Node *) te->expr),
exprCollation((Node *) te->expr));
splan->setParam = list_make1_int(prm->paramid);
isInitPlan = true;
result = (Node *) prm;
}
else if (splan->parParam == NIL && subLinkType == ROWCOMPARE_SUBLINK)
{
/* Adjust the Params */
List *params;
Assert(testexpr != NULL);
params = generate_subquery_params(root,
plan->targetlist,
&splan->paramIds);
result = convert_testexpr(root,
testexpr,
params);
splan->setParam = list_copy(splan->paramIds);
isInitPlan = true;
/*
* The executable expression is returned to become part of the outer
* plan's expression tree; it is not kept in the initplan node.
*/
}
else
{
/*
* Adjust the Params in the testexpr, unless caller said it's not
* needed.
*/
if (testexpr && adjust_testexpr)
{
List *params;
params = generate_subquery_params(root,
plan->targetlist,
&splan->paramIds);
splan->testexpr = convert_testexpr(root,
testexpr,
params);
}
else
splan->testexpr = testexpr;
/*
* We can't convert subplans of ALL_SUBLINK or ANY_SUBLINK types to
* initPlans, even when they are uncorrelated or undirect correlated,
* because we need to scan the output of the subplan for each outer
* tuple. But if it's a not-direct-correlated IN (= ANY) test, we
* might be able to use a hashtable to avoid comparing all the tuples.
*/
if (subLinkType == ANY_SUBLINK &&
splan->parParam == NIL &&
subplan_is_hashable(plan) &&
testexpr_is_hashable(splan->testexpr))
splan->useHashTable = true;
/*
* Otherwise, we have the option to tack a Material node onto the top
* of the subplan, to reduce the cost of reading it repeatedly. This
* is pointless for a direct-correlated subplan, since we'd have to
* recompute its results each time anyway. For uncorrelated/undirect
* correlated subplans, we add Material unless the subplan's top plan
* node would materialize its output anyway. Also, if enable_material
* is false, then the user does not want us to materialize anything
* unnecessarily, so we don't.
*/
else if (splan->parParam == NIL && enable_material &&
!ExecMaterializesOutput(nodeTag(plan)))
plan = materialize_finished_plan(plan);
result = (Node *) splan;
isInitPlan = false;
}
/*
* Add the subplan and its PlannerInfo to the global lists.
*/
root->glob->subplans = lappend(root->glob->subplans, plan);
root->glob->subroots = lappend(root->glob->subroots, subroot);
splan->plan_id = list_length(root->glob->subplans);
if (isInitPlan)
root->init_plans = lappend(root->init_plans, splan);
/*
* A parameterless subplan (not initplan) should be prepared to handle
* REWIND efficiently. If it has direct parameters then there's no point
* since it'll be reset on each scan anyway; and if it's an initplan then
* there's no point since it won't get re-run without parameter changes
* anyway. The input of a hashed subplan doesn't need REWIND either.
*/
if (splan->parParam == NIL && !isInitPlan && !splan->useHashTable)
root->glob->rewindPlanIDs = bms_add_member(root->glob->rewindPlanIDs,
splan->plan_id);
/* Label the subplan for EXPLAIN purposes */
if (isInitPlan)
{
ListCell *lc;
int offset;
splan->plan_name = palloc(32 + 12 * list_length(splan->setParam));
sprintf(splan->plan_name, "InitPlan %d (returns ", splan->plan_id);
offset = strlen(splan->plan_name);
foreach(lc, splan->setParam)
{
sprintf(splan->plan_name + offset, "$%d%s",
lfirst_int(lc),
lnext(lc) ? "," : "");
offset += strlen(splan->plan_name + offset);
}
sprintf(splan->plan_name + offset, ")");
}
else
{
splan->plan_name = palloc(32);
sprintf(splan->plan_name, "SubPlan %d", splan->plan_id);
}
/* Lastly, fill in the cost estimates for use later */
cost_subplan(root, splan, plan);
return result;
}
| JoinExpr* convert_ANY_sublink_to_join | ( | PlannerInfo * | root, | |
| SubLink * | sublink, | |||
| Relids | available_rels | |||
| ) |
Definition at line 1165 of file subselect.c.
References addRangeTableEntryForSubquery(), JoinExpr::alias, ANY_SUBLINK, Assert, bms_is_empty(), bms_is_subset(), contain_vars_of_level(), contain_volatile_functions(), convert_testexpr(), generate_subquery_vars(), JoinExpr::isNatural, JoinExpr::jointype, lappend(), JoinExpr::larg, list_length(), makeAlias(), makeNode, NIL, NULL, PlannerInfo::parse, parse(), pull_varnos(), JoinExpr::quals, JoinExpr::rarg, Query::rtable, JoinExpr::rtindex, SubLink::subLinkType, SubLink::subselect, SubLink::testexpr, and JoinExpr::usingClause.
Referenced by pull_up_sublinks_qual_recurse().
{
JoinExpr *result;
Query *parse = root->parse;
Query *subselect = (Query *) sublink->subselect;
Relids upper_varnos;
int rtindex;
RangeTblEntry *rte;
RangeTblRef *rtr;
List *subquery_vars;
Node *quals;
Assert(sublink->subLinkType == ANY_SUBLINK);
/*
* The sub-select must not refer to any Vars of the parent query. (Vars of
* higher levels should be okay, though.)
*/
if (contain_vars_of_level((Node *) subselect, 1))
return NULL;
/*
* The test expression must contain some Vars of the parent query, else
* it's not gonna be a join. (Note that it won't have Vars referring to
* the subquery, rather Params.)
*/
upper_varnos = pull_varnos(sublink->testexpr);
if (bms_is_empty(upper_varnos))
return NULL;
/*
* However, it can't refer to anything outside available_rels.
*/
if (!bms_is_subset(upper_varnos, available_rels))
return NULL;
/*
* The combining operators and left-hand expressions mustn't be volatile.
*/
if (contain_volatile_functions(sublink->testexpr))
return NULL;
/*
* Okay, pull up the sub-select into upper range table.
*
* We rely here on the assumption that the outer query has no references
* to the inner (necessarily true, other than the Vars that we build
* below). Therefore this is a lot easier than what pull_up_subqueries has
* to go through.
*/
rte = addRangeTableEntryForSubquery(NULL,
subselect,
makeAlias("ANY_subquery", NIL),
false,
false);
parse->rtable = lappend(parse->rtable, rte);
rtindex = list_length(parse->rtable);
/*
* Form a RangeTblRef for the pulled-up sub-select.
*/
rtr = makeNode(RangeTblRef);
rtr->rtindex = rtindex;
/*
* Build a list of Vars representing the subselect outputs.
*/
subquery_vars = generate_subquery_vars(root,
subselect->targetList,
rtindex);
/*
* Build the new join's qual expression, replacing Params with these Vars.
*/
quals = convert_testexpr(root, sublink->testexpr, subquery_vars);
/*
* And finally, build the JoinExpr node.
*/
result = makeNode(JoinExpr);
result->jointype = JOIN_SEMI;
result->isNatural = false;
result->larg = NULL; /* caller must fill this in */
result->rarg = (Node *) rtr;
result->usingClause = NIL;
result->quals = quals;
result->alias = NULL;
result->rtindex = 0; /* we don't need an RTE for it */
return result;
}
| JoinExpr* convert_EXISTS_sublink_to_join | ( | PlannerInfo * | root, | |
| SubLink * | sublink, | |||
| bool | under_not, | |||
| Relids | available_rels | |||
| ) |
Definition at line 1266 of file subselect.c.
References JoinExpr::alias, Assert, bms_add_member(), bms_first_member(), bms_free(), bms_is_empty(), bms_is_subset(), contain_vars_of_level(), contain_volatile_functions(), copyObject(), Query::cteList, EXISTS_SUBLINK, FromExpr::fromlist, IncrementVarSublevelsUp(), JoinExpr::isNatural, JOIN_ANTI, Query::jointree, JoinExpr::jointype, JoinExpr::larg, linitial, list_concat(), list_length(), makeNode, NIL, NULL, OffsetVarNodes(), PlannerInfo::parse, parse(), pull_varnos(), JoinExpr::quals, FromExpr::quals, JoinExpr::rarg, Query::rtable, JoinExpr::rtindex, simplify_EXISTS_query(), SubLink::subLinkType, SubLink::subselect, and JoinExpr::usingClause.
Referenced by pull_up_sublinks_qual_recurse().
{
JoinExpr *result;
Query *parse = root->parse;
Query *subselect = (Query *) sublink->subselect;
Node *whereClause;
int rtoffset;
int varno;
Relids clause_varnos;
Relids upper_varnos;
Assert(sublink->subLinkType == EXISTS_SUBLINK);
/*
* Can't flatten if it contains WITH. (We could arrange to pull up the
* WITH into the parent query's cteList, but that risks changing the
* semantics, since a WITH ought to be executed once per associated query
* call.) Note that convert_ANY_sublink_to_join doesn't have to reject
* this case, since it just produces a subquery RTE that doesn't have to
* get flattened into the parent query.
*/
if (subselect->cteList)
return NULL;
/*
* Copy the subquery so we can modify it safely (see comments in
* make_subplan).
*/
subselect = (Query *) copyObject(subselect);
/*
* See if the subquery can be simplified based on the knowledge that it's
* being used in EXISTS(). If we aren't able to get rid of its
* targetlist, we have to fail, because the pullup operation leaves us
* with noplace to evaluate the targetlist.
*/
if (!simplify_EXISTS_query(subselect))
return NULL;
/*
* The subquery must have a nonempty jointree, else we won't have a join.
*/
if (subselect->jointree->fromlist == NIL)
return NULL;
/*
* Separate out the WHERE clause. (We could theoretically also remove
* top-level plain JOIN/ON clauses, but it's probably not worth the
* trouble.)
*/
whereClause = subselect->jointree->quals;
subselect->jointree->quals = NULL;
/*
* The rest of the sub-select must not refer to any Vars of the parent
* query. (Vars of higher levels should be okay, though.)
*/
if (contain_vars_of_level((Node *) subselect, 1))
return NULL;
/*
* On the other hand, the WHERE clause must contain some Vars of the
* parent query, else it's not gonna be a join.
*/
if (!contain_vars_of_level(whereClause, 1))
return NULL;
/*
* We don't risk optimizing if the WHERE clause is volatile, either.
*/
if (contain_volatile_functions(whereClause))
return NULL;
/*
* Prepare to pull up the sub-select into top range table.
*
* We rely here on the assumption that the outer query has no references
* to the inner (necessarily true). Therefore this is a lot easier than
* what pull_up_subqueries has to go through.
*
* In fact, it's even easier than what convert_ANY_sublink_to_join has to
* do. The machinations of simplify_EXISTS_query ensured that there is
* nothing interesting in the subquery except an rtable and jointree, and
* even the jointree FromExpr no longer has quals. So we can just append
* the rtable to our own and use the FromExpr in our jointree. But first,
* adjust all level-zero varnos in the subquery to account for the rtable
* merger.
*/
rtoffset = list_length(parse->rtable);
OffsetVarNodes((Node *) subselect, rtoffset, 0);
OffsetVarNodes(whereClause, rtoffset, 0);
/*
* Upper-level vars in subquery will now be one level closer to their
* parent than before; in particular, anything that had been level 1
* becomes level zero.
*/
IncrementVarSublevelsUp((Node *) subselect, -1, 1);
IncrementVarSublevelsUp(whereClause, -1, 1);
/*
* Now that the WHERE clause is adjusted to match the parent query
* environment, we can easily identify all the level-zero rels it uses.
* The ones <= rtoffset belong to the upper query; the ones > rtoffset do
* not.
*/
clause_varnos = pull_varnos(whereClause);
upper_varnos = NULL;
while ((varno = bms_first_member(clause_varnos)) >= 0)
{
if (varno <= rtoffset)
upper_varnos = bms_add_member(upper_varnos, varno);
}
bms_free(clause_varnos);
Assert(!bms_is_empty(upper_varnos));
/*
* Now that we've got the set of upper-level varnos, we can make the last
* check: only available_rels can be referenced.
*/
if (!bms_is_subset(upper_varnos, available_rels))
return NULL;
/* Now we can attach the modified subquery rtable to the parent */
parse->rtable = list_concat(parse->rtable, subselect->rtable);
/*
* And finally, build the JoinExpr node.
*/
result = makeNode(JoinExpr);
result->jointype = under_not ? JOIN_ANTI : JOIN_SEMI;
result->isNatural = false;
result->larg = NULL; /* caller must fill this in */
/* flatten out the FromExpr node if it's useless */
if (list_length(subselect->jointree->fromlist) == 1)
result->rarg = (Node *) linitial(subselect->jointree->fromlist);
else
result->rarg = (Node *) subselect->jointree;
result->usingClause = NIL;
result->quals = whereClause;
result->alias = NULL;
result->rtindex = 0; /* we don't need an RTE for it */
return result;
}
| static Query * convert_EXISTS_to_ANY | ( | PlannerInfo * | root, | |
| Query * | subselect, | |||
| Node ** | testexpr, | |||
| List ** | paramIds | |||
| ) | [static] |
Definition at line 1488 of file subselect.c.
References OpExpr::args, Assert, BOOLOID, canonicalize_qual(), contain_aggs_of_level(), contain_subplans(), contain_vars_of_level(), contain_volatile_functions(), eval_const_expressions(), exprCollation(), exprType(), exprTypmod(), forthree, generate_new_param(), get_commutator(), Query::hasAggs, hash_ok_operator(), IncrementVarSublevelsUp(), OpExpr::inputcollid, InvalidOid, IsA, Query::jointree, lappend(), lappend_int(), lappend_oid(), lfirst, lfirst_oid, linitial, list_head(), lnext, lsecond, make_ands_explicit(), make_ands_implicit(), make_opclause(), makeTargetEntry(), NIL, NULL, OidIsValid, OpExpr::opno, PlannerInfo::parse, FromExpr::quals, and Query::targetList.
Referenced by make_subplan().
{
Node *whereClause;
List *leftargs,
*rightargs,
*opids,
*opcollations,
*newWhere,
*tlist,
*testlist,
*paramids;
ListCell *lc,
*rc,
*oc,
*cc;
AttrNumber resno;
/*
* Query must not require a targetlist, since we have to insert a new one.
* Caller should have dealt with the case already.
*/
Assert(subselect->targetList == NIL);
/*
* Separate out the WHERE clause. (We could theoretically also remove
* top-level plain JOIN/ON clauses, but it's probably not worth the
* trouble.)
*/
whereClause = subselect->jointree->quals;
subselect->jointree->quals = NULL;
/*
* The rest of the sub-select must not refer to any Vars of the parent
* query. (Vars of higher levels should be okay, though.)
*
* Note: we need not check for Aggrefs separately because we know the
* sub-select is as yet unoptimized; any uplevel Aggref must therefore
* contain an uplevel Var reference. This is not the case below ...
*/
if (contain_vars_of_level((Node *) subselect, 1))
return NULL;
/*
* We don't risk optimizing if the WHERE clause is volatile, either.
*/
if (contain_volatile_functions(whereClause))
return NULL;
/*
* Clean up the WHERE clause by doing const-simplification etc on it.
* Aside from simplifying the processing we're about to do, this is
* important for being able to pull chunks of the WHERE clause up into the
* parent query. Since we are invoked partway through the parent's
* preprocess_expression() work, earlier steps of preprocess_expression()
* wouldn't get applied to the pulled-up stuff unless we do them here. For
* the parts of the WHERE clause that get put back into the child query,
* this work is partially duplicative, but it shouldn't hurt.
*
* Note: we do not run flatten_join_alias_vars. This is OK because any
* parent aliases were flattened already, and we're not going to pull any
* child Vars (of any description) into the parent.
*
* Note: passing the parent's root to eval_const_expressions is
* technically wrong, but we can get away with it since only the
* boundParams (if any) are used, and those would be the same in a
* subroot.
*/
whereClause = eval_const_expressions(root, whereClause);
whereClause = (Node *) canonicalize_qual((Expr *) whereClause);
whereClause = (Node *) make_ands_implicit((Expr *) whereClause);
/*
* We now have a flattened implicit-AND list of clauses, which we try to
* break apart into "outervar = innervar" hash clauses. Anything that
* can't be broken apart just goes back into the newWhere list. Note that
* we aren't trying hard yet to ensure that we have only outer or only
* inner on each side; we'll check that if we get to the end.
*/
leftargs = rightargs = opids = opcollations = newWhere = NIL;
foreach(lc, (List *) whereClause)
{
OpExpr *expr = (OpExpr *) lfirst(lc);
if (IsA(expr, OpExpr) &&
hash_ok_operator(expr))
{
Node *leftarg = (Node *) linitial(expr->args);
Node *rightarg = (Node *) lsecond(expr->args);
if (contain_vars_of_level(leftarg, 1))
{
leftargs = lappend(leftargs, leftarg);
rightargs = lappend(rightargs, rightarg);
opids = lappend_oid(opids, expr->opno);
opcollations = lappend_oid(opcollations, expr->inputcollid);
continue;
}
if (contain_vars_of_level(rightarg, 1))
{
/*
* We must commute the clause to put the outer var on the
* left, because the hashing code in nodeSubplan.c expects
* that. This probably shouldn't ever fail, since hashable
* operators ought to have commutators, but be paranoid.
*/
expr->opno = get_commutator(expr->opno);
if (OidIsValid(expr->opno) && hash_ok_operator(expr))
{
leftargs = lappend(leftargs, rightarg);
rightargs = lappend(rightargs, leftarg);
opids = lappend_oid(opids, expr->opno);
opcollations = lappend_oid(opcollations, expr->inputcollid);
continue;
}
/* If no commutator, no chance to optimize the WHERE clause */
return NULL;
}
}
/* Couldn't handle it as a hash clause */
newWhere = lappend(newWhere, expr);
}
/*
* If we didn't find anything we could convert, fail.
*/
if (leftargs == NIL)
return NULL;
/*
* There mustn't be any parent Vars or Aggs in the stuff that we intend to
* put back into the child query. Note: you might think we don't need to
* check for Aggs separately, because an uplevel Agg must contain an
* uplevel Var in its argument. But it is possible that the uplevel Var
* got optimized away by eval_const_expressions. Consider
*
* SUM(CASE WHEN false THEN uplevelvar ELSE 0 END)
*/
if (contain_vars_of_level((Node *) newWhere, 1) ||
contain_vars_of_level((Node *) rightargs, 1))
return NULL;
if (root->parse->hasAggs &&
(contain_aggs_of_level((Node *) newWhere, 1) ||
contain_aggs_of_level((Node *) rightargs, 1)))
return NULL;
/*
* And there can't be any child Vars in the stuff we intend to pull up.
* (Note: we'd need to check for child Aggs too, except we know the child
* has no aggs at all because of simplify_EXISTS_query's check. The same
* goes for window functions.)
*/
if (contain_vars_of_level((Node *) leftargs, 0))
return NULL;
/*
* Also reject sublinks in the stuff we intend to pull up. (It might be
* possible to support this, but doesn't seem worth the complication.)
*/
if (contain_subplans((Node *) leftargs))
return NULL;
/*
* Okay, adjust the sublevelsup in the stuff we're pulling up.
*/
IncrementVarSublevelsUp((Node *) leftargs, -1, 1);
/*
* Put back any child-level-only WHERE clauses.
*/
if (newWhere)
subselect->jointree->quals = (Node *) make_ands_explicit(newWhere);
/*
* Build a new targetlist for the child that emits the expressions we
* need. Concurrently, build a testexpr for the parent using Params to
* reference the child outputs. (Since we generate Params directly here,
* there will be no need to convert the testexpr in build_subplan.)
*/
tlist = testlist = paramids = NIL;
resno = 1;
/* there's no "forfour" so we have to chase one of the lists manually */
cc = list_head(opcollations);
forthree(lc, leftargs, rc, rightargs, oc, opids)
{
Node *leftarg = (Node *) lfirst(lc);
Node *rightarg = (Node *) lfirst(rc);
Oid opid = lfirst_oid(oc);
Oid opcollation = lfirst_oid(cc);
Param *param;
cc = lnext(cc);
param = generate_new_param(root,
exprType(rightarg),
exprTypmod(rightarg),
exprCollation(rightarg));
tlist = lappend(tlist,
makeTargetEntry((Expr *) rightarg,
resno++,
NULL,
false));
testlist = lappend(testlist,
make_opclause(opid, BOOLOID, false,
(Expr *) leftarg, (Expr *) param,
InvalidOid, opcollation));
paramids = lappend_int(paramids, param->paramid);
}
/* Put everything where it should go, and we're done */
subselect->targetList = tlist;
*testexpr = (Node *) make_ands_explicit(testlist);
*paramIds = paramids;
return subselect;
}
| static Node * convert_testexpr | ( | PlannerInfo * | root, | |
| Node * | testexpr, | |||
| List * | subst_nodes | |||
| ) | [static] |
Definition at line 866 of file subselect.c.
References convert_testexpr_mutator(), convert_testexpr_context::root, and convert_testexpr_context::subst_nodes.
Referenced by build_subplan(), and convert_ANY_sublink_to_join().
{
convert_testexpr_context context;
context.root = root;
context.subst_nodes = subst_nodes;
return convert_testexpr_mutator(testexpr, &context);
}
| static Node * convert_testexpr_mutator | ( | Node * | node, | |
| convert_testexpr_context * | context | |||
| ) | [static] |
Definition at line 878 of file subselect.c.
References copyObject(), elog, ERROR, expression_tree_mutator(), IsA, list_length(), list_nth(), NULL, PARAM_SUBLINK, Param::paramid, Param::paramkind, and convert_testexpr_context::subst_nodes.
Referenced by convert_testexpr().
{
if (node == NULL)
return NULL;
if (IsA(node, Param))
{
Param *param = (Param *) node;
if (param->paramkind == PARAM_SUBLINK)
{
if (param->paramid <= 0 ||
param->paramid > list_length(context->subst_nodes))
elog(ERROR, "unexpected PARAM_SUBLINK ID: %d", param->paramid);
/*
* We copy the list item to avoid having doubly-linked
* substructure in the modified parse tree. This is probably
* unnecessary when it's a Param, but be safe.
*/
return (Node *) copyObject(list_nth(context->subst_nodes,
param->paramid - 1));
}
}
return expression_tree_mutator(node,
convert_testexpr_mutator,
(void *) context);
}
| static Bitmapset * finalize_plan | ( | PlannerInfo * | root, | |
| Plan * | plan, | |||
| Bitmapset * | valid_params, | |||
| Bitmapset * | scan_params | |||
| ) | [static] |
Definition at line 2036 of file subselect.c.
References Plan::allParam, bms_add_member(), bms_add_members(), bms_copy(), bms_del_member(), bms_difference(), bms_free(), bms_is_empty(), bms_is_subset(), bms_union(), elog, ModifyTable::epqParam, ERROR, Plan::extParam, finalize_primnode(), PlannerInfo::glob, Plan::lefttree, lfirst, list_length(), list_nth(), nodeTag, NULL, finalize_primnode_context::paramids, NestLoopParam::paramno, ModifyTable::plans, Plan::qual, ModifyTable::returningLists, Plan::righttree, finalize_primnode_context::root, PlannerGlobal::subplans, T_Agg, T_Append, T_BitmapAnd, T_BitmapHeapScan, T_BitmapIndexScan, T_BitmapOr, T_CteScan, T_ForeignScan, T_FunctionScan, T_Group, T_Hash, T_HashJoin, T_IndexOnlyScan, T_IndexScan, T_Limit, T_LockRows, T_Material, T_MergeAppend, T_MergeJoin, T_ModifyTable, T_NestLoop, T_RecursiveUnion, T_Result, T_SeqScan, T_SetOp, T_Sort, T_SubqueryScan, T_TidScan, T_Unique, T_ValuesScan, T_WindowAgg, T_WorkTableScan, and Plan::targetlist.
Referenced by SS_finalize_plan().
{
finalize_primnode_context context;
int locally_added_param;
Bitmapset *nestloop_params;
Bitmapset *child_params;
if (plan == NULL)
return NULL;
context.root = root;
context.paramids = NULL; /* initialize set to empty */
locally_added_param = -1; /* there isn't one */
nestloop_params = NULL; /* there aren't any */
/*
* When we call finalize_primnode, context.paramids sets are automatically
* merged together. But when recursing to self, we have to do it the hard
* way. We want the paramids set to include params in subplans as well as
* at this level.
*/
/* Find params in targetlist and qual */
finalize_primnode((Node *) plan->targetlist, &context);
finalize_primnode((Node *) plan->qual, &context);
/* Check additional node-type-specific fields */
switch (nodeTag(plan))
{
case T_Result:
finalize_primnode(((Result *) plan)->resconstantqual,
&context);
break;
case T_SeqScan:
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_IndexScan:
finalize_primnode((Node *) ((IndexScan *) plan)->indexqual,
&context);
finalize_primnode((Node *) ((IndexScan *) plan)->indexorderby,
&context);
/*
* we need not look at indexqualorig, since it will have the same
* param references as indexqual. Likewise, we can ignore
* indexorderbyorig.
*/
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_IndexOnlyScan:
finalize_primnode((Node *) ((IndexOnlyScan *) plan)->indexqual,
&context);
finalize_primnode((Node *) ((IndexOnlyScan *) plan)->indexorderby,
&context);
/*
* we need not look at indextlist, since it cannot contain Params.
*/
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_BitmapIndexScan:
finalize_primnode((Node *) ((BitmapIndexScan *) plan)->indexqual,
&context);
/*
* we need not look at indexqualorig, since it will have the same
* param references as indexqual.
*/
break;
case T_BitmapHeapScan:
finalize_primnode((Node *) ((BitmapHeapScan *) plan)->bitmapqualorig,
&context);
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_TidScan:
finalize_primnode((Node *) ((TidScan *) plan)->tidquals,
&context);
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_SubqueryScan:
/*
* In a SubqueryScan, SS_finalize_plan has already been run on the
* subplan by the inner invocation of subquery_planner, so there's
* no need to do it again. Instead, just pull out the subplan's
* extParams list, which represents the params it needs from my
* level and higher levels.
*/
context.paramids = bms_add_members(context.paramids,
((SubqueryScan *) plan)->subplan->extParam);
/* We need scan_params too, though */
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_FunctionScan:
finalize_primnode(((FunctionScan *) plan)->funcexpr,
&context);
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_ValuesScan:
finalize_primnode((Node *) ((ValuesScan *) plan)->values_lists,
&context);
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_CteScan:
{
/*
* You might think we should add the node's cteParam to
* paramids, but we shouldn't because that param is just a
* linkage mechanism for multiple CteScan nodes for the same
* CTE; it is never used for changed-param signaling. What we
* have to do instead is to find the referenced CTE plan and
* incorporate its external paramids, so that the correct
* things will happen if the CTE references outer-level
* variables. See test cases for bug #4902.
*/
int plan_id = ((CteScan *) plan)->ctePlanId;
Plan *cteplan;
/* so, do this ... */
if (plan_id < 1 || plan_id > list_length(root->glob->subplans))
elog(ERROR, "could not find plan for CteScan referencing plan ID %d",
plan_id);
cteplan = (Plan *) list_nth(root->glob->subplans, plan_id - 1);
context.paramids =
bms_add_members(context.paramids, cteplan->extParam);
#ifdef NOT_USED
/* ... but not this */
context.paramids =
bms_add_member(context.paramids,
((CteScan *) plan)->cteParam);
#endif
context.paramids = bms_add_members(context.paramids,
scan_params);
}
break;
case T_WorkTableScan:
context.paramids =
bms_add_member(context.paramids,
((WorkTableScan *) plan)->wtParam);
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_ForeignScan:
finalize_primnode((Node *) ((ForeignScan *) plan)->fdw_exprs,
&context);
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_ModifyTable:
{
ModifyTable *mtplan = (ModifyTable *) plan;
ListCell *l;
/* Force descendant scan nodes to reference epqParam */
locally_added_param = mtplan->epqParam;
valid_params = bms_add_member(bms_copy(valid_params),
locally_added_param);
scan_params = bms_add_member(bms_copy(scan_params),
locally_added_param);
finalize_primnode((Node *) mtplan->returningLists,
&context);
foreach(l, mtplan->plans)
{
context.paramids =
bms_add_members(context.paramids,
finalize_plan(root,
(Plan *) lfirst(l),
valid_params,
scan_params));
}
}
break;
case T_Append:
{
ListCell *l;
foreach(l, ((Append *) plan)->appendplans)
{
context.paramids =
bms_add_members(context.paramids,
finalize_plan(root,
(Plan *) lfirst(l),
valid_params,
scan_params));
}
}
break;
case T_MergeAppend:
{
ListCell *l;
foreach(l, ((MergeAppend *) plan)->mergeplans)
{
context.paramids =
bms_add_members(context.paramids,
finalize_plan(root,
(Plan *) lfirst(l),
valid_params,
scan_params));
}
}
break;
case T_BitmapAnd:
{
ListCell *l;
foreach(l, ((BitmapAnd *) plan)->bitmapplans)
{
context.paramids =
bms_add_members(context.paramids,
finalize_plan(root,
(Plan *) lfirst(l),
valid_params,
scan_params));
}
}
break;
case T_BitmapOr:
{
ListCell *l;
foreach(l, ((BitmapOr *) plan)->bitmapplans)
{
context.paramids =
bms_add_members(context.paramids,
finalize_plan(root,
(Plan *) lfirst(l),
valid_params,
scan_params));
}
}
break;
case T_NestLoop:
{
ListCell *l;
finalize_primnode((Node *) ((Join *) plan)->joinqual,
&context);
/* collect set of params that will be passed to right child */
foreach(l, ((NestLoop *) plan)->nestParams)
{
NestLoopParam *nlp = (NestLoopParam *) lfirst(l);
nestloop_params = bms_add_member(nestloop_params,
nlp->paramno);
}
}
break;
case T_MergeJoin:
finalize_primnode((Node *) ((Join *) plan)->joinqual,
&context);
finalize_primnode((Node *) ((MergeJoin *) plan)->mergeclauses,
&context);
break;
case T_HashJoin:
finalize_primnode((Node *) ((Join *) plan)->joinqual,
&context);
finalize_primnode((Node *) ((HashJoin *) plan)->hashclauses,
&context);
break;
case T_Limit:
finalize_primnode(((Limit *) plan)->limitOffset,
&context);
finalize_primnode(((Limit *) plan)->limitCount,
&context);
break;
case T_RecursiveUnion:
/* child nodes are allowed to reference wtParam */
locally_added_param = ((RecursiveUnion *) plan)->wtParam;
valid_params = bms_add_member(bms_copy(valid_params),
locally_added_param);
/* wtParam does *not* get added to scan_params */
break;
case T_LockRows:
/* Force descendant scan nodes to reference epqParam */
locally_added_param = ((LockRows *) plan)->epqParam;
valid_params = bms_add_member(bms_copy(valid_params),
locally_added_param);
scan_params = bms_add_member(bms_copy(scan_params),
locally_added_param);
break;
case T_WindowAgg:
finalize_primnode(((WindowAgg *) plan)->startOffset,
&context);
finalize_primnode(((WindowAgg *) plan)->endOffset,
&context);
break;
case T_Hash:
case T_Agg:
case T_Material:
case T_Sort:
case T_Unique:
case T_SetOp:
case T_Group:
break;
default:
elog(ERROR, "unrecognized node type: %d",
(int) nodeTag(plan));
}
/* Process left and right child plans, if any */
child_params = finalize_plan(root,
plan->lefttree,
valid_params,
scan_params);
context.paramids = bms_add_members(context.paramids, child_params);
if (nestloop_params)
{
/* right child can reference nestloop_params as well as valid_params */
child_params = finalize_plan(root,
plan->righttree,
bms_union(nestloop_params, valid_params),
scan_params);
/* ... and they don't count as parameters used at my level */
child_params = bms_difference(child_params, nestloop_params);
bms_free(nestloop_params);
}
else
{
/* easy case */
child_params = finalize_plan(root,
plan->righttree,
valid_params,
scan_params);
}
context.paramids = bms_add_members(context.paramids, child_params);
/*
* Any locally generated parameter doesn't count towards its generating
* plan node's external dependencies. (Note: if we changed valid_params
* and/or scan_params, we leak those bitmapsets; not worth the notational
* trouble to clean them up.)
*/
if (locally_added_param >= 0)
{
context.paramids = bms_del_member(context.paramids,
locally_added_param);
}
/* Now we have all the paramids */
if (!bms_is_subset(context.paramids, valid_params))
elog(ERROR, "plan should not reference subplan's variable");
/*
* Note: by definition, extParam and allParam should have the same value
* in any plan node that doesn't have child initPlans. We set them equal
* here, and later SS_finalize_plan will update them properly in node(s)
* that it attaches initPlans to.
*
* For speed at execution time, make sure extParam/allParam are actually
* NULL if they are empty sets.
*/
if (bms_is_empty(context.paramids))
{
plan->extParam = NULL;
plan->allParam = NULL;
}
else
{
plan->extParam = context.paramids;
plan->allParam = bms_copy(context.paramids);
}
return plan->allParam;
}
| static bool finalize_primnode | ( | Node * | node, | |
| finalize_primnode_context * | context | |||
| ) | [static] |
Definition at line 2436 of file subselect.c.
References SubPlan::args, bms_add_member(), bms_copy(), bms_del_member(), bms_join(), expression_tree_walker(), Plan::extParam, IsA, lfirst_int, NULL, PARAM_EXEC, SubPlan::paramIds, finalize_primnode_context::paramids, SubPlan::parParam, planner_subplan_get_plan, finalize_primnode_context::root, and SubPlan::testexpr.
Referenced by finalize_plan().
{
if (node == NULL)
return false;
if (IsA(node, Param))
{
if (((Param *) node)->paramkind == PARAM_EXEC)
{
int paramid = ((Param *) node)->paramid;
context->paramids = bms_add_member(context->paramids, paramid);
}
return false; /* no more to do here */
}
if (IsA(node, SubPlan))
{
SubPlan *subplan = (SubPlan *) node;
Plan *plan = planner_subplan_get_plan(context->root, subplan);
ListCell *lc;
Bitmapset *subparamids;
/* Recurse into the testexpr, but not into the Plan */
finalize_primnode(subplan->testexpr, context);
/*
* Remove any param IDs of output parameters of the subplan that were
* referenced in the testexpr. These are not interesting for
* parameter change signaling since we always re-evaluate the subplan.
* Note that this wouldn't work too well if there might be uses of the
* same param IDs elsewhere in the plan, but that can't happen because
* generate_new_param never tries to merge params.
*/
foreach(lc, subplan->paramIds)
{
context->paramids = bms_del_member(context->paramids,
lfirst_int(lc));
}
/* Also examine args list */
finalize_primnode((Node *) subplan->args, context);
/*
* Add params needed by the subplan to paramids, but excluding those
* we will pass down to it.
*/
subparamids = bms_copy(plan->extParam);
foreach(lc, subplan->parParam)
{
subparamids = bms_del_member(subparamids, lfirst_int(lc));
}
context->paramids = bms_join(context->paramids, subparamids);
return false; /* no more to do here */
}
return expression_tree_walker(node, finalize_primnode,
(void *) context);
}
| static Param* generate_new_param | ( | PlannerInfo * | root, | |
| Oid | paramtype, | |||
| int32 | paramtypmod, | |||
| Oid | paramcollation | |||
| ) | [static] |
Definition at line 345 of file subselect.c.
References PlannerInfo::glob, Param::location, makeNode, PlannerGlobal::nParamExec, Param::paramcollid, Param::paramid, Param::paramkind, Param::paramtype, and Param::paramtypmod.
Referenced by build_subplan(), convert_EXISTS_to_ANY(), generate_subquery_params(), and SS_make_initplan_from_plan().
{
Param *retval;
retval = makeNode(Param);
retval->paramkind = PARAM_EXEC;
retval->paramid = root->glob->nParamExec++;
retval->paramtype = paramtype;
retval->paramtypmod = paramtypmod;
retval->paramcollid = paramcollation;
retval->location = -1;
return retval;
}
| static List * generate_subquery_params | ( | PlannerInfo * | root, | |
| List * | tlist, | |||
| List ** | paramIds | |||
| ) | [static] |
Definition at line 799 of file subselect.c.
References TargetEntry::expr, exprCollation(), exprType(), exprTypmod(), generate_new_param(), lappend(), lappend_int(), lfirst, Param::paramid, and TargetEntry::resjunk.
Referenced by build_subplan().
{
List *result;
List *ids;
ListCell *lc;
result = ids = NIL;
foreach(lc, tlist)
{
TargetEntry *tent = (TargetEntry *) lfirst(lc);
Param *param;
if (tent->resjunk)
continue;
param = generate_new_param(root,
exprType((Node *) tent->expr),
exprTypmod((Node *) tent->expr),
exprCollation((Node *) tent->expr));
result = lappend(result, param);
ids = lappend_int(ids, param->paramid);
}
*paramIds = ids;
return result;
}
| static List * generate_subquery_vars | ( | PlannerInfo * | root, | |
| List * | tlist, | |||
| Index | varno | |||
| ) | [static] |
Definition at line 832 of file subselect.c.
References lappend(), lfirst, makeVarFromTargetEntry(), and TargetEntry::resjunk.
Referenced by convert_ANY_sublink_to_join().
{
List *result;
ListCell *lc;
result = NIL;
foreach(lc, tlist)
{
TargetEntry *tent = (TargetEntry *) lfirst(lc);
Var *var;
if (tent->resjunk)
continue;
var = makeVarFromTargetEntry(varno, tent);
result = lappend(result, var);
}
return result;
}
| static void get_first_col_type | ( | Plan * | plan, | |
| Oid * | coltype, | |||
| int32 * | coltypmod, | |||
| Oid * | colcollation | |||
| ) | [static] |
Definition at line 385 of file subselect.c.
References Assert, TargetEntry::expr, exprCollation(), exprType(), exprTypmod(), IsA, linitial, TargetEntry::resjunk, and Plan::targetlist.
Referenced by build_subplan(), SS_make_initplan_from_plan(), and SS_process_ctes().
{
/* In cases such as EXISTS, tlist might be empty; arbitrarily use VOID */
if (plan->targetlist)
{
TargetEntry *tent = (TargetEntry *) linitial(plan->targetlist);
Assert(IsA(tent, TargetEntry));
if (!tent->resjunk)
{
*coltype = exprType((Node *) tent->expr);
*coltypmod = exprTypmod((Node *) tent->expr);
*colcollation = exprCollation((Node *) tent->expr);
return;
}
}
*coltype = VOIDOID;
*coltypmod = -1;
*colcollation = InvalidOid;
}
Definition at line 977 of file subselect.c.
References OpExpr::args, ARRAY_EQ_OP, elog, ERROR, exprType(), func_strict(), GETSTRUCT, HeapTupleIsValid, linitial, list_length(), ObjectIdGetDatum, op_hashjoinable(), OPEROID, OpExpr::opno, ReleaseSysCache(), and SearchSysCache1.
Referenced by convert_EXISTS_to_ANY(), and testexpr_is_hashable().
{
Oid opid = expr->opno;
/* quick out if not a binary operator */
if (list_length(expr->args) != 2)
return false;
if (opid == ARRAY_EQ_OP)
{
/* array_eq is strict, but must check input type to ensure hashable */
/* XXX record_eq will need same treatment when it becomes hashable */
Node *leftarg = linitial(expr->args);
return op_hashjoinable(opid, exprType(leftarg));
}
else
{
/* else must look up the operator properties */
HeapTuple tup;
Form_pg_operator optup;
tup = SearchSysCache1(OPEROID, ObjectIdGetDatum(opid));
if (!HeapTupleIsValid(tup))
elog(ERROR, "cache lookup failed for operator %u", opid);
optup = (Form_pg_operator) GETSTRUCT(tup);
if (!optup->oprcanhash || !func_strict(optup->oprcode))
{
ReleaseSysCache(tup);
return false;
}
ReleaseSysCache(tup);
return true;
}
}
| static Node* make_subplan | ( | PlannerInfo * | root, | |
| Query * | orig_subquery, | |||
| SubLinkType | subLinkType, | |||
| Node * | testexpr, | |||
| bool | isTopQual | |||
| ) | [static] |
Definition at line 425 of file subselect.c.
References ALL_SUBLINK, ANY_SUBLINK, Assert, build_subplan(), convert_EXISTS_to_ANY(), copyObject(), EXISTS_SUBLINK, PlannerInfo::glob, IsA, list_make2, makeNode, NIL, SubPlan::paramIds, SubPlan::parParam, PlannerInfo::plan_params, simplify_EXISTS_query(), subplan_is_hashable(), AlternativeSubPlan::subplans, subquery_planner(), and SubPlan::useHashTable.
Referenced by process_sublinks_mutator().
{
Query *subquery;
bool simple_exists = false;
double tuple_fraction;
Plan *plan;
PlannerInfo *subroot;
List *plan_params;
Node *result;
/*
* Copy the source Query node. This is a quick and dirty kluge to resolve
* the fact that the parser can generate trees with multiple links to the
* same sub-Query node, but the planner wants to scribble on the Query.
* Try to clean this up when we do querytree redesign...
*/
subquery = (Query *) copyObject(orig_subquery);
/*
* If it's an EXISTS subplan, we might be able to simplify it.
*/
if (subLinkType == EXISTS_SUBLINK)
simple_exists = simplify_EXISTS_query(subquery);
/*
* For an EXISTS subplan, tell lower-level planner to expect that only the
* first tuple will be retrieved. For ALL and ANY subplans, we will be
* able to stop evaluating if the test condition fails or matches, so very
* often not all the tuples will be retrieved; for lack of a better idea,
* specify 50% retrieval. For EXPR and ROWCOMPARE subplans, use default
* behavior (we're only expecting one row out, anyway).
*
* NOTE: if you change these numbers, also change cost_subplan() in
* path/costsize.c.
*
* XXX If an ANY subplan is uncorrelated, build_subplan may decide to hash
* its output. In that case it would've been better to specify full
* retrieval. At present, however, we can only check hashability after
* we've made the subplan :-(. (Determining whether it'll fit in work_mem
* is the really hard part.) Therefore, we don't want to be too
* optimistic about the percentage of tuples retrieved, for fear of
* selecting a plan that's bad for the materialization case.
*/
if (subLinkType == EXISTS_SUBLINK)
tuple_fraction = 1.0; /* just like a LIMIT 1 */
else if (subLinkType == ALL_SUBLINK ||
subLinkType == ANY_SUBLINK)
tuple_fraction = 0.5; /* 50% */
else
tuple_fraction = 0.0; /* default behavior */
/* plan_params should not be in use in current query level */
Assert(root->plan_params == NIL);
/*
* Generate the plan for the subquery.
*/
plan = subquery_planner(root->glob, subquery,
root,
false, tuple_fraction,
&subroot);
/* Isolate the params needed by this specific subplan */
plan_params = root->plan_params;
root->plan_params = NIL;
/* And convert to SubPlan or InitPlan format. */
result = build_subplan(root, plan, subroot, plan_params,
subLinkType, testexpr, true, isTopQual);
/*
* If it's a correlated EXISTS with an unimportant targetlist, we might be
* able to transform it to the equivalent of an IN and then implement it
* by hashing. We don't have enough information yet to tell which way is
* likely to be better (it depends on the expected number of executions of
* the EXISTS qual, and we are much too early in planning the outer query
* to be able to guess that). So we generate both plans, if possible, and
* leave it to the executor to decide which to use.
*/
if (simple_exists && IsA(result, SubPlan))
{
Node *newtestexpr;
List *paramIds;
/* Make a second copy of the original subquery */
subquery = (Query *) copyObject(orig_subquery);
/* and re-simplify */
simple_exists = simplify_EXISTS_query(subquery);
Assert(simple_exists);
/* See if it can be converted to an ANY query */
subquery = convert_EXISTS_to_ANY(root, subquery,
&newtestexpr, ¶mIds);
if (subquery)
{
/* Generate the plan for the ANY subquery; we'll need all rows */
plan = subquery_planner(root->glob, subquery,
root,
false, 0.0,
&subroot);
/* Isolate the params needed by this specific subplan */
plan_params = root->plan_params;
root->plan_params = NIL;
/* Now we can check if it'll fit in work_mem */
if (subplan_is_hashable(plan))
{
SubPlan *hashplan;
AlternativeSubPlan *asplan;
/* OK, convert to SubPlan format. */
hashplan = (SubPlan *) build_subplan(root, plan, subroot,
plan_params,
ANY_SUBLINK, newtestexpr,
false, true);
/* Check we got what we expected */
Assert(IsA(hashplan, SubPlan));
Assert(hashplan->parParam == NIL);
Assert(hashplan->useHashTable);
/* build_subplan won't have filled in paramIds */
hashplan->paramIds = paramIds;
/* Leave it to the executor to decide which plan to use */
asplan = makeNode(AlternativeSubPlan);
asplan->subplans = list_make2(result, hashplan);
result = (Node *) asplan;
}
}
}
return result;
}
| static Node * process_sublinks_mutator | ( | Node * | node, | |
| process_sublinks_context * | context | |||
| ) | [static] |
Definition at line 1780 of file subselect.c.
References and_clause(), Assert, expression_tree_mutator(), IsA, process_sublinks_context::isTopQual, lappend(), lfirst, list_concat(), make_andclause(), make_orclause(), make_subplan(), NULL, or_clause(), process_sublinks_context::root, SubLink::subLinkType, SubLink::subselect, and SubLink::testexpr.
Referenced by SS_process_sublinks().
{
process_sublinks_context locContext;
locContext.root = context->root;
if (node == NULL)
return NULL;
if (IsA(node, SubLink))
{
SubLink *sublink = (SubLink *) node;
Node *testexpr;
/*
* First, recursively process the lefthand-side expressions, if any.
* They're not top-level anymore.
*/
locContext.isTopQual = false;
testexpr = process_sublinks_mutator(sublink->testexpr, &locContext);
/*
* Now build the SubPlan node and make the expr to return.
*/
return make_subplan(context->root,
(Query *) sublink->subselect,
sublink->subLinkType,
testexpr,
context->isTopQual);
}
/*
* Don't recurse into the arguments of an outer PHV or aggregate here. Any
* SubLinks in the arguments have to be dealt with at the outer query
* level; they'll be handled when build_subplan collects the PHV or Aggref
* into the arguments to be passed down to the current subplan.
*/
if (IsA(node, PlaceHolderVar))
{
if (((PlaceHolderVar *) node)->phlevelsup > 0)
return node;
}
else if (IsA(node, Aggref))
{
if (((Aggref *) node)->agglevelsup > 0)
return node;
}
/*
* We should never see a SubPlan expression in the input (since this is
* the very routine that creates 'em to begin with). We shouldn't find
* ourselves invoked directly on a Query, either.
*/
Assert(!IsA(node, SubPlan));
Assert(!IsA(node, AlternativeSubPlan));
Assert(!IsA(node, Query));
/*
* Because make_subplan() could return an AND or OR clause, we have to
* take steps to preserve AND/OR flatness of a qual. We assume the input
* has been AND/OR flattened and so we need no recursion here.
*
* (Due to the coding here, we will not get called on the List subnodes of
* an AND; and the input is *not* yet in implicit-AND format. So no check
* is needed for a bare List.)
*
* Anywhere within the top-level AND/OR clause structure, we can tell
* make_subplan() that NULL and FALSE are interchangeable. So isTopQual
* propagates down in both cases. (Note that this is unlike the meaning
* of "top level qual" used in most other places in Postgres.)
*/
if (and_clause(node))
{
List *newargs = NIL;
ListCell *l;
/* Still at qual top-level */
locContext.isTopQual = context->isTopQual;
foreach(l, ((BoolExpr *) node)->args)
{
Node *newarg;
newarg = process_sublinks_mutator(lfirst(l), &locContext);
if (and_clause(newarg))
newargs = list_concat(newargs, ((BoolExpr *) newarg)->args);
else
newargs = lappend(newargs, newarg);
}
return (Node *) make_andclause(newargs);
}
if (or_clause(node))
{
List *newargs = NIL;
ListCell *l;
/* Still at qual top-level */
locContext.isTopQual = context->isTopQual;
foreach(l, ((BoolExpr *) node)->args)
{
Node *newarg;
newarg = process_sublinks_mutator(lfirst(l), &locContext);
if (or_clause(newarg))
newargs = list_concat(newargs, ((BoolExpr *) newarg)->args);
else
newargs = lappend(newargs, newarg);
}
return (Node *) make_orclause(newargs);
}
/*
* If we recurse down through anything other than an AND or OR node, we
* are definitely not at top qual level anymore.
*/
locContext.isTopQual = false;
return expression_tree_mutator(node,
process_sublinks_mutator,
(void *) &locContext);
}
| static Node * replace_correlation_vars_mutator | ( | Node * | node, | |
| PlannerInfo * | root | |||
| ) | [static] |
Definition at line 1737 of file subselect.c.
References expression_tree_mutator(), IsA, NULL, replace_outer_agg(), replace_outer_placeholdervar(), and replace_outer_var().
Referenced by SS_replace_correlation_vars().
{
if (node == NULL)
return NULL;
if (IsA(node, Var))
{
if (((Var *) node)->varlevelsup > 0)
return (Node *) replace_outer_var(root, (Var *) node);
}
if (IsA(node, PlaceHolderVar))
{
if (((PlaceHolderVar *) node)->phlevelsup > 0)
return (Node *) replace_outer_placeholdervar(root,
(PlaceHolderVar *) node);
}
if (IsA(node, Aggref))
{
if (((Aggref *) node)->agglevelsup > 0)
return (Node *) replace_outer_agg(root, (Aggref *) node);
}
return expression_tree_mutator(node,
replace_correlation_vars_mutator,
(void *) root);
}
| static Param* replace_outer_agg | ( | PlannerInfo * | root, | |
| Aggref * | agg | |||
| ) | [static] |
Definition at line 300 of file subselect.c.
References Aggref::agglevelsup, Assert, copyObject(), PlannerInfo::glob, IncrementVarSublevelsUp(), PlannerParamItem::item, lappend(), Param::location, makeNode, PlannerGlobal::nParamExec, Param::paramcollid, Param::paramid, PlannerParamItem::paramId, Param::paramkind, Param::paramtype, Param::paramtypmod, PlannerInfo::parent_root, PlannerInfo::plan_params, and PlannerInfo::query_level.
Referenced by replace_correlation_vars_mutator().
{
Param *retval;
PlannerParamItem *pitem;
Index levelsup;
Assert(agg->agglevelsup > 0 && agg->agglevelsup < root->query_level);
/* Find the query level the Aggref belongs to */
for (levelsup = agg->agglevelsup; levelsup > 0; levelsup--)
root = root->parent_root;
/*
* It does not seem worthwhile to try to match duplicate outer aggs. Just
* make a new slot every time.
*/
agg = (Aggref *) copyObject(agg);
IncrementVarSublevelsUp((Node *) agg, -((int) agg->agglevelsup), 0);
Assert(agg->agglevelsup == 0);
pitem = makeNode(PlannerParamItem);
pitem->item = (Node *) agg;
pitem->paramId = root->glob->nParamExec++;
root->plan_params = lappend(root->plan_params, pitem);
retval = makeNode(Param);
retval->paramkind = PARAM_EXEC;
retval->paramid = pitem->paramId;
retval->paramtype = agg->aggtype;
retval->paramtypmod = -1;
retval->paramcollid = agg->aggcollid;
retval->location = agg->location;
return retval;
}
| static Param* replace_outer_placeholdervar | ( | PlannerInfo * | root, | |
| PlaceHolderVar * | phv | |||
| ) | [static] |
Definition at line 247 of file subselect.c.
References Assert, assign_param_for_placeholdervar(), exprCollation(), exprType(), exprTypmod(), i, Param::location, makeNode, Param::paramcollid, Param::paramid, Param::paramkind, Param::paramtype, Param::paramtypmod, PlaceHolderVar::phexpr, PlaceHolderVar::phlevelsup, and PlannerInfo::query_level.
Referenced by replace_correlation_vars_mutator().
{
Param *retval;
int i;
Assert(phv->phlevelsup > 0 && phv->phlevelsup < root->query_level);
/* Find the PHV in the appropriate plan_params, or add it if not present */
i = assign_param_for_placeholdervar(root, phv);
retval = makeNode(Param);
retval->paramkind = PARAM_EXEC;
retval->paramid = i;
retval->paramtype = exprType((Node *) phv->phexpr);
retval->paramtypmod = exprTypmod((Node *) phv->phexpr);
retval->paramcollid = exprCollation((Node *) phv->phexpr);
retval->location = -1;
return retval;
}
| static Param* replace_outer_var | ( | PlannerInfo * | root, | |
| Var * | var | |||
| ) | [static] |
Definition at line 142 of file subselect.c.
References Assert, assign_param_for_var(), i, Var::location, Param::location, makeNode, Param::paramcollid, Param::paramid, Param::paramkind, Param::paramtype, Param::paramtypmod, PlannerInfo::query_level, Var::varcollid, Var::varlevelsup, Var::vartype, and Var::vartypmod.
Referenced by replace_correlation_vars_mutator().
{
Param *retval;
int i;
Assert(var->varlevelsup > 0 && var->varlevelsup < root->query_level);
/* Find the Var in the appropriate plan_params, or add it if not present */
i = assign_param_for_var(root, var);
retval = makeNode(Param);
retval->paramkind = PARAM_EXEC;
retval->paramid = i;
retval->paramtype = var->vartype;
retval->paramtypmod = var->vartypmod;
retval->paramcollid = var->varcollid;
retval->location = var->location;
return retval;
}
Definition at line 1430 of file subselect.c.
References CMD_SELECT, Query::commandType, Query::distinctClause, expression_returns_set(), Query::groupClause, Query::hasAggs, Query::hasDistinctOn, Query::hasModifyingCTE, Query::hasWindowFuncs, Query::havingQual, Query::limitCount, Query::limitOffset, Query::rowMarks, Query::setOperations, Query::sortClause, Query::targetList, and Query::windowClause.
Referenced by convert_EXISTS_sublink_to_join(), and make_subplan().
{
/*
* We don't try to simplify at all if the query uses set operations,
* aggregates, modifying CTEs, HAVING, LIMIT/OFFSET, or FOR UPDATE/SHARE;
* none of these seem likely in normal usage and their possible effects
* are complex.
*/
if (query->commandType != CMD_SELECT ||
query->setOperations ||
query->hasAggs ||
query->hasWindowFuncs ||
query->hasModifyingCTE ||
query->havingQual ||
query->limitOffset ||
query->limitCount ||
query->rowMarks)
return false;
/*
* Mustn't throw away the targetlist if it contains set-returning
* functions; those could affect whether zero rows are returned!
*/
if (expression_returns_set((Node *) query->targetList))
return false;
/*
* Otherwise, we can throw away the targetlist, as well as any GROUP,
* WINDOW, DISTINCT, and ORDER BY clauses; none of those clauses will
* change a nonzero-rows result to zero rows or vice versa. (Furthermore,
* since our parsetree representation of these clauses depends on the
* targetlist, we'd better throw them away if we drop the targetlist.)
*/
query->targetList = NIL;
query->groupClause = NIL;
query->windowClause = NIL;
query->distinctClause = NIL;
query->sortClause = NIL;
query->hasDistinctOn = false;
return true;
}
| int SS_assign_special_param | ( | PlannerInfo * | root | ) |
Definition at line 370 of file subselect.c.
References PlannerInfo::glob, and PlannerGlobal::nParamExec.
Referenced by inheritance_planner(), SS_process_ctes(), and subquery_planner().
{
return root->glob->nParamExec++;
}
| void SS_finalize_plan | ( | PlannerInfo * | root, | |
| Plan * | plan, | |||
| bool | attach_initplans | |||
| ) |
Definition at line 1913 of file subselect.c.
References Plan::allParam, bms_add_member(), bms_add_members(), bms_copy(), bms_del_members(), bms_free(), bms_is_empty(), Plan::extParam, finalize_plan(), PlannerInfo::init_plans, Plan::initPlan, lfirst, lfirst_int, NULL, PlannerParamItem::paramId, PlannerInfo::parent_root, SubPlan::per_call_cost, PlannerInfo::plan_params, planner_subplan_get_plan, SubPlan::setParam, Plan::startup_cost, SubPlan::startup_cost, Plan::total_cost, and PlannerInfo::wt_param_id.
Referenced by SS_make_initplan_from_plan(), and subquery_planner().
{
Bitmapset *valid_params,
*initExtParam,
*initSetParam;
Cost initplan_cost;
PlannerInfo *proot;
ListCell *l;
/*
* Examine any initPlans to determine the set of external params they
* reference, the set of output params they supply, and their total cost.
* We'll use at least some of this info below. (Note we are assuming that
* finalize_plan doesn't touch the initPlans.)
*
* In the case where attach_initplans is false, we are assuming that the
* existing initPlans are siblings that might supply params needed by the
* current plan.
*/
initExtParam = initSetParam = NULL;
initplan_cost = 0;
foreach(l, root->init_plans)
{
SubPlan *initsubplan = (SubPlan *) lfirst(l);
Plan *initplan = planner_subplan_get_plan(root, initsubplan);
ListCell *l2;
initExtParam = bms_add_members(initExtParam, initplan->extParam);
foreach(l2, initsubplan->setParam)
{
initSetParam = bms_add_member(initSetParam, lfirst_int(l2));
}
initplan_cost += initsubplan->startup_cost + initsubplan->per_call_cost;
}
/*
* Now determine the set of params that are validly referenceable in this
* query level; to wit, those available from outer query levels plus the
* output parameters of any local initPlans. (We do not include output
* parameters of regular subplans. Those should only appear within the
* testexpr of SubPlan nodes, and are taken care of locally within
* finalize_primnode. Likewise, special parameters that are generated by
* nodes such as ModifyTable are handled within finalize_plan.)
*/
valid_params = bms_copy(initSetParam);
for (proot = root->parent_root; proot != NULL; proot = proot->parent_root)
{
/* Include ordinary Var/PHV/Aggref params */
foreach(l, proot->plan_params)
{
PlannerParamItem *pitem = (PlannerParamItem *) lfirst(l);
valid_params = bms_add_member(valid_params, pitem->paramId);
}
/* Include any outputs of outer-level initPlans */
foreach(l, proot->init_plans)
{
SubPlan *initsubplan = (SubPlan *) lfirst(l);
ListCell *l2;
foreach(l2, initsubplan->setParam)
{
valid_params = bms_add_member(valid_params, lfirst_int(l2));
}
}
/* Include worktable ID, if a recursive query is being planned */
if (proot->wt_param_id >= 0)
valid_params = bms_add_member(valid_params, proot->wt_param_id);
}
/*
* Now recurse through plan tree.
*/
(void) finalize_plan(root, plan, valid_params, NULL);
bms_free(valid_params);
/*
* Finally, attach any initPlans to the topmost plan node, and add their
* extParams to the topmost node's, too. However, any setParams of the
* initPlans should not be present in the topmost node's extParams, only
* in its allParams. (As of PG 8.1, it's possible that some initPlans
* have extParams that are setParams of other initPlans, so we have to
* take care of this situation explicitly.)
*
* We also add the eval cost of each initPlan to the startup cost of the
* top node. This is a conservative overestimate, since in fact each
* initPlan might be executed later than plan startup, or even not at all.
*/
if (attach_initplans)
{
plan->initPlan = root->init_plans;
root->init_plans = NIL; /* make sure they're not attached twice */
/* allParam must include all these params */
plan->allParam = bms_add_members(plan->allParam, initExtParam);
plan->allParam = bms_add_members(plan->allParam, initSetParam);
/* extParam must include any child extParam */
plan->extParam = bms_add_members(plan->extParam, initExtParam);
/* but extParam shouldn't include any setParams */
plan->extParam = bms_del_members(plan->extParam, initSetParam);
/* ensure extParam is exactly NULL if it's empty */
if (bms_is_empty(plan->extParam))
plan->extParam = NULL;
plan->startup_cost += initplan_cost;
plan->total_cost += initplan_cost;
}
}
| Param* SS_make_initplan_from_plan | ( | PlannerInfo * | root, | |
| Plan * | plan, | |||
| Oid | resulttype, | |||
| int32 | resulttypmod, | |||
| Oid | resultcollation | |||
| ) |
Definition at line 2505 of file subselect.c.
References cost_subplan(), SubPlan::firstColCollation, SubPlan::firstColType, SubPlan::firstColTypmod, generate_new_param(), get_first_col_type(), PlannerInfo::glob, PlannerInfo::init_plans, lappend(), list_length(), list_make1_int, makeNode, palloc(), Param::paramid, SubPlan::plan_id, SubPlan::plan_name, SubPlan::setParam, SS_finalize_plan(), SubPlan::subLinkType, PlannerGlobal::subplans, and PlannerGlobal::subroots.
Referenced by make_agg_subplan().
{
SubPlan *node;
Param *prm;
/*
* We must run SS_finalize_plan(), since that's normally done before a
* subplan gets put into the initplan list. Tell it not to attach any
* pre-existing initplans to this one, since they are siblings not
* children of this initplan. (This is something else that could perhaps
* be cleaner if we did extParam/allParam processing in setrefs.c instead
* of here? See notes for materialize_finished_plan.)
*/
/*
* Build extParam/allParam sets for plan nodes.
*/
SS_finalize_plan(root, plan, false);
/*
* Add the subplan and its PlannerInfo to the global lists.
*/
root->glob->subplans = lappend(root->glob->subplans, plan);
root->glob->subroots = lappend(root->glob->subroots, root);
/*
* Create a SubPlan node and add it to the outer list of InitPlans. Note
* it has to appear after any other InitPlans it might depend on (see
* comments in ExecReScan).
*/
node = makeNode(SubPlan);
node->subLinkType = EXPR_SUBLINK;
get_first_col_type(plan, &node->firstColType, &node->firstColTypmod,
&node->firstColCollation);
node->plan_id = list_length(root->glob->subplans);
root->init_plans = lappend(root->init_plans, node);
/*
* The node can't have any inputs (since it's an initplan), so the
* parParam and args lists remain empty.
*/
cost_subplan(root, node, plan);
/*
* Make a Param that will be the subplan's output.
*/
prm = generate_new_param(root, resulttype, resulttypmod, resultcollation);
node->setParam = list_make1_int(prm->paramid);
/* Label the subplan for EXPLAIN purposes */
node->plan_name = palloc(64);
sprintf(node->plan_name, "InitPlan %d (returns $%d)",
node->plan_id, prm->paramid);
return prm;
}
| void SS_process_ctes | ( | PlannerInfo * | root | ) |
Definition at line 1022 of file subselect.c.
References SubPlan::args, Assert, CMD_SELECT, copyObject(), cost_subplan(), PlannerInfo::cte_plan_ids, Query::cteList, CommonTableExpr::ctename, CommonTableExpr::ctequery, CommonTableExpr::cterecursive, CommonTableExpr::cterefcount, elog, ERROR, SubPlan::firstColCollation, SubPlan::firstColType, SubPlan::firstColTypmod, get_first_col_type(), PlannerInfo::glob, PlannerInfo::init_plans, lappend(), lappend_int(), lfirst, list_length(), list_make1_int, makeNode, NIL, palloc(), SubPlan::paramIds, SubPlan::parParam, PlannerInfo::parse, SubPlan::plan_id, SubPlan::plan_name, PlannerInfo::plan_params, SubPlan::setParam, splan, SS_assign_special_param(), SubPlan::subLinkType, PlannerGlobal::subplans, subquery_planner(), PlannerGlobal::subroots, SubPlan::testexpr, SubPlan::unknownEqFalse, and SubPlan::useHashTable.
Referenced by subquery_planner().
{
ListCell *lc;
Assert(root->cte_plan_ids == NIL);
foreach(lc, root->parse->cteList)
{
CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
CmdType cmdType = ((Query *) cte->ctequery)->commandType;
Query *subquery;
Plan *plan;
PlannerInfo *subroot;
SubPlan *splan;
int paramid;
/*
* Ignore SELECT CTEs that are not actually referenced anywhere.
*/
if (cte->cterefcount == 0 && cmdType == CMD_SELECT)
{
/* Make a dummy entry in cte_plan_ids */
root->cte_plan_ids = lappend_int(root->cte_plan_ids, -1);
continue;
}
/*
* Copy the source Query node. Probably not necessary, but let's keep
* this similar to make_subplan.
*/
subquery = (Query *) copyObject(cte->ctequery);
/* plan_params should not be in use in current query level */
Assert(root->plan_params == NIL);
/*
* Generate the plan for the CTE query. Always plan for full
* retrieval --- we don't have enough info to predict otherwise.
*/
plan = subquery_planner(root->glob, subquery,
root,
cte->cterecursive, 0.0,
&subroot);
/*
* Since the current query level doesn't yet contain any RTEs, it
* should not be possible for the CTE to have requested parameters of
* this level.
*/
if (root->plan_params)
elog(ERROR, "unexpected outer reference in CTE query");
/*
* Make a SubPlan node for it. This is just enough unlike
* build_subplan that we can't share code.
*
* Note plan_id, plan_name, and cost fields are set further down.
*/
splan = makeNode(SubPlan);
splan->subLinkType = CTE_SUBLINK;
splan->testexpr = NULL;
splan->paramIds = NIL;
get_first_col_type(plan, &splan->firstColType, &splan->firstColTypmod,
&splan->firstColCollation);
splan->useHashTable = false;
splan->unknownEqFalse = false;
splan->setParam = NIL;
splan->parParam = NIL;
splan->args = NIL;
/*
* The node can't have any inputs (since it's an initplan), so the
* parParam and args lists remain empty. (It could contain references
* to earlier CTEs' output param IDs, but CTE outputs are not
* propagated via the args list.)
*/
/*
* Assign a param ID to represent the CTE's output. No ordinary
* "evaluation" of this param slot ever happens, but we use the param
* ID for setParam/chgParam signaling just as if the CTE plan were
* returning a simple scalar output. (Also, the executor abuses the
* ParamExecData slot for this param ID for communication among
* multiple CteScan nodes that might be scanning this CTE.)
*/
paramid = SS_assign_special_param(root);
splan->setParam = list_make1_int(paramid);
/*
* Add the subplan and its PlannerInfo to the global lists.
*/
root->glob->subplans = lappend(root->glob->subplans, plan);
root->glob->subroots = lappend(root->glob->subroots, subroot);
splan->plan_id = list_length(root->glob->subplans);
root->init_plans = lappend(root->init_plans, splan);
root->cte_plan_ids = lappend_int(root->cte_plan_ids, splan->plan_id);
/* Label the subplan for EXPLAIN purposes */
splan->plan_name = palloc(4 + strlen(cte->ctename) + 1);
sprintf(splan->plan_name, "CTE %s", cte->ctename);
/* Lastly, fill in the cost estimates for use later */
cost_subplan(root, splan, plan);
}
}
| Node* SS_process_sublinks | ( | PlannerInfo * | root, | |
| Node * | expr, | |||
| bool | isQual | |||
| ) |
Definition at line 1770 of file subselect.c.
References process_sublinks_context::isTopQual, process_sublinks_mutator(), and process_sublinks_context::root.
Referenced by build_subplan(), and preprocess_expression().
{
process_sublinks_context context;
context.root = root;
context.isTopQual = isQual;
return process_sublinks_mutator(expr, &context);
}
| Node* SS_replace_correlation_vars | ( | PlannerInfo * | root, | |
| Node * | expr | |||
| ) |
Definition at line 1730 of file subselect.c.
References replace_correlation_vars_mutator().
Referenced by preprocess_expression().
{
/* No setup needed for tree walk, so away we go */
return replace_correlation_vars_mutator(expr, root);
}
Definition at line 911 of file subselect.c.
References MAXALIGN, Plan::plan_rows, Plan::plan_width, and work_mem.
Referenced by build_subplan(), and make_subplan().
{
double subquery_size;
/*
* The estimated size of the subquery result must fit in work_mem. (Note:
* we use sizeof(HeapTupleHeaderData) here even though the tuples will
* actually be stored as MinimalTuples; this provides some fudge factor
* for hashtable overhead.)
*/
subquery_size = plan->plan_rows *
(MAXALIGN(plan->plan_width) + MAXALIGN(sizeof(HeapTupleHeaderData)));
if (subquery_size > work_mem * 1024L)
return false;
return true;
}
Definition at line 933 of file subselect.c.
References and_clause(), hash_ok_operator(), IsA, and lfirst.
Referenced by build_subplan().
{
/*
* The testexpr must be a single OpExpr, or an AND-clause containing only
* OpExprs.
*
* The combining operators must be hashable and strict. The need for
* hashability is obvious, since we want to use hashing. Without
* strictness, behavior in the presence of nulls is too unpredictable. We
* actually must assume even more than plain strictness: they can't yield
* NULL for non-null inputs, either (see nodeSubplan.c). However, hash
* indexes and hash joins assume that too.
*/
if (testexpr && IsA(testexpr, OpExpr))
{
if (hash_ok_operator((OpExpr *) testexpr))
return true;
}
else if (and_clause(testexpr))
{
ListCell *l;
foreach(l, ((BoolExpr *) testexpr)->args)
{
Node *andarg = (Node *) lfirst(l);
if (!IsA(andarg, OpExpr))
return false;
if (!hash_ok_operator((OpExpr *) andarg))
return false;
}
return true;
}
return false;
}
1.7.1