startup_cost = ofpinfo->rel_startup_cost;
startup_cost += aggcosts.transCost.startup;
startup_cost += aggcosts.transCost.per_tuple * input_rows;
+ startup_cost += aggcosts.finalCost.startup;
startup_cost += (cpu_operator_cost * numGroupCols) * input_rows;
/*-----
*-----
*/
run_cost = ofpinfo->rel_total_cost - ofpinfo->rel_startup_cost;
- run_cost += aggcosts.finalCost * numGroups;
+ run_cost += aggcosts.finalCost.per_tuple * numGroups;
run_cost += cpu_tuple_cost * numGroups;
/* Account for the eval cost of HAVING quals, if any */
simplify. Ensure rigorous equivalence between the simplified
expression and an actual execution of the target function.
</para>
+
+ <para>
+ For target functions that return boolean, it is often useful to estimate
+ the fraction of rows that will be selected by a WHERE clause using that
+ function. This can be done by a support function that implements
+ the <literal>SupportRequestSelectivity</literal> request type.
+ </para>
+
+ <para>
+ If the target function's runtime is highly dependent on its inputs,
+ it may be useful to provide a non-constant cost estimate for it.
+ This can be done by a support function that implements
+ the <literal>SupportRequestCost</literal> request type.
+ </para>
+
+ <para>
+ For target functions that return sets, it is often useful to provide
+ a non-constant estimate for the number of rows that will be returned.
+ This can be done by a support function that implements
+ the <literal>SupportRequestRows</literal> request type.
+ </para>
</sect1>
if (IsA(clause, DistinctExpr))
s1 = 1.0 - s1;
}
+ else if (is_funcclause(clause))
+ {
+ FuncExpr *funcclause = (FuncExpr *) clause;
+
+ /* Try to get an estimate from the support function, if any */
+ s1 = function_selectivity(root,
+ funcclause->funcid,
+ funcclause->args,
+ funcclause->inputcollid,
+ treat_as_join_clause(clause, rinfo,
+ varRelid, sjinfo),
+ varRelid,
+ jointype,
+ sjinfo);
+ }
else if (IsA(clause, ScalarArrayOpExpr))
{
/* Use node specific selectivity calculation function */
/*
* The transCost.per_tuple component of aggcosts should be charged once
* per input tuple, corresponding to the costs of evaluating the aggregate
- * transfns and their input expressions (with any startup cost of course
- * charged but once). The finalCost component is charged once per output
- * tuple, corresponding to the costs of evaluating the finalfns.
+ * transfns and their input expressions. The finalCost.per_tuple component
+ * is charged once per output tuple, corresponding to the costs of
+ * evaluating the finalfns. Startup costs are of course charged but once.
*
* If we are grouping, we charge an additional cpu_operator_cost per
* grouping column per input tuple for grouping comparisons.
startup_cost = input_total_cost;
startup_cost += aggcosts->transCost.startup;
startup_cost += aggcosts->transCost.per_tuple * input_tuples;
- startup_cost += aggcosts->finalCost;
+ startup_cost += aggcosts->finalCost.startup;
+ startup_cost += aggcosts->finalCost.per_tuple;
/* we aren't grouping */
total_cost = startup_cost + cpu_tuple_cost;
output_tuples = 1;
total_cost += aggcosts->transCost.startup;
total_cost += aggcosts->transCost.per_tuple * input_tuples;
total_cost += (cpu_operator_cost * numGroupCols) * input_tuples;
- total_cost += aggcosts->finalCost * numGroups;
+ total_cost += aggcosts->finalCost.startup;
+ total_cost += aggcosts->finalCost.per_tuple * numGroups;
total_cost += cpu_tuple_cost * numGroups;
output_tuples = numGroups;
}
startup_cost += aggcosts->transCost.startup;
startup_cost += aggcosts->transCost.per_tuple * input_tuples;
startup_cost += (cpu_operator_cost * numGroupCols) * input_tuples;
+ startup_cost += aggcosts->finalCost.startup;
total_cost = startup_cost;
- total_cost += aggcosts->finalCost * numGroups;
+ total_cost += aggcosts->finalCost.per_tuple * numGroups;
total_cost += cpu_tuple_cost * numGroups;
output_tuples = numGroups;
}
Cost wfunccost;
QualCost argcosts;
- wfunccost = get_func_cost(wfunc->winfnoid) * cpu_operator_cost;
+ argcosts.startup = argcosts.per_tuple = 0;
+ add_function_cost(root, wfunc->winfnoid, (Node *) wfunc,
+ &argcosts);
+ startup_cost += argcosts.startup;
+ wfunccost = argcosts.per_tuple;
/* also add the input expressions' cost to per-input-row costs */
cost_qual_eval_node(&argcosts, (Node *) wfunc->args, root);
*/
if (IsA(node, FuncExpr))
{
- context->total.per_tuple +=
- get_func_cost(((FuncExpr *) node)->funcid) * cpu_operator_cost;
+ add_function_cost(context->root, ((FuncExpr *) node)->funcid, node,
+ &context->total);
}
else if (IsA(node, OpExpr) ||
IsA(node, DistinctExpr) ||
{
/* rely on struct equivalence to treat these all alike */
set_opfuncid((OpExpr *) node);
- context->total.per_tuple +=
- get_func_cost(((OpExpr *) node)->opfuncid) * cpu_operator_cost;
+ add_function_cost(context->root, ((OpExpr *) node)->opfuncid, node,
+ &context->total);
}
else if (IsA(node, ScalarArrayOpExpr))
{
*/
ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) node;
Node *arraynode = (Node *) lsecond(saop->args);
+ QualCost sacosts;
set_sa_opfuncid(saop);
- context->total.per_tuple += get_func_cost(saop->opfuncid) *
- cpu_operator_cost * estimate_array_length(arraynode) * 0.5;
+ sacosts.startup = sacosts.per_tuple = 0;
+ add_function_cost(context->root, saop->opfuncid, NULL,
+ &sacosts);
+ context->total.startup += sacosts.startup;
+ context->total.per_tuple += sacosts.per_tuple *
+ estimate_array_length(arraynode) * 0.5;
}
else if (IsA(node, Aggref) ||
IsA(node, WindowFunc))
/* check the result type's input function */
getTypeInputInfo(iocoerce->resulttype,
&iofunc, &typioparam);
- context->total.per_tuple += get_func_cost(iofunc) * cpu_operator_cost;
+ add_function_cost(context->root, iofunc, NULL,
+ &context->total);
/* check the input type's output function */
getTypeOutputInfo(exprType((Node *) iocoerce->arg),
&iofunc, &typisvarlena);
- context->total.per_tuple += get_func_cost(iofunc) * cpu_operator_cost;
+ add_function_cost(context->root, iofunc, NULL,
+ &context->total);
}
else if (IsA(node, ArrayCoerceExpr))
{
{
Oid opid = lfirst_oid(lc);
- context->total.per_tuple += get_func_cost(get_opcode(opid)) *
- cpu_operator_cost;
+ add_function_cost(context->root, get_opcode(opid), NULL,
+ &context->total);
}
}
else if (IsA(node, MinMaxExpr) ||
foreach(lc, rte->functions)
{
RangeTblFunction *rtfunc = (RangeTblFunction *) lfirst(lc);
- double ntup = expression_returns_set_rows(rtfunc->funcexpr);
+ double ntup = expression_returns_set_rows(root, rtfunc->funcexpr);
if (ntup > rel->tuples)
rel->tuples = ntup;
#include "optimizer/clauses.h"
#include "optimizer/cost.h"
#include "optimizer/optimizer.h"
+#include "optimizer/plancat.h"
#include "optimizer/planmain.h"
-#include "optimizer/prep.h"
#include "parser/analyze.h"
#include "parser/parse_agg.h"
#include "parser/parse_coerce.h"
if (DO_AGGSPLIT_COMBINE(context->aggsplit))
{
/* charge for combining previously aggregated states */
- costs->transCost.per_tuple += get_func_cost(aggcombinefn) * cpu_operator_cost;
+ add_function_cost(context->root, aggcombinefn, NULL,
+ &costs->transCost);
}
else
- costs->transCost.per_tuple += get_func_cost(aggtransfn) * cpu_operator_cost;
+ add_function_cost(context->root, aggtransfn, NULL,
+ &costs->transCost);
if (DO_AGGSPLIT_DESERIALIZE(context->aggsplit) &&
OidIsValid(aggdeserialfn))
- costs->transCost.per_tuple += get_func_cost(aggdeserialfn) * cpu_operator_cost;
+ add_function_cost(context->root, aggdeserialfn, NULL,
+ &costs->transCost);
if (DO_AGGSPLIT_SERIALIZE(context->aggsplit) &&
OidIsValid(aggserialfn))
- costs->finalCost += get_func_cost(aggserialfn) * cpu_operator_cost;
+ add_function_cost(context->root, aggserialfn, NULL,
+ &costs->finalCost);
if (!DO_AGGSPLIT_SKIPFINAL(context->aggsplit) &&
OidIsValid(aggfinalfn))
- costs->finalCost += get_func_cost(aggfinalfn) * cpu_operator_cost;
+ add_function_cost(context->root, aggfinalfn, NULL,
+ &costs->finalCost);
/*
* These costs are incurred only by the initial aggregate node, so we
{
cost_qual_eval_node(&argcosts, (Node *) aggref->aggdirectargs,
context->root);
- costs->transCost.startup += argcosts.startup;
- costs->finalCost += argcosts.per_tuple;
+ costs->finalCost.startup += argcosts.startup;
+ costs->finalCost.per_tuple += argcosts.per_tuple;
}
/*
* Note: keep this in sync with expression_returns_set() in nodes/nodeFuncs.c.
*/
double
-expression_returns_set_rows(Node *clause)
+expression_returns_set_rows(PlannerInfo *root, Node *clause)
{
if (clause == NULL)
return 1.0;
FuncExpr *expr = (FuncExpr *) clause;
if (expr->funcretset)
- return clamp_row_est(get_func_rows(expr->funcid));
+ return clamp_row_est(get_function_rows(root, expr->funcid, clause));
}
if (IsA(clause, OpExpr))
{
if (expr->opretset)
{
set_opfuncid(expr);
- return clamp_row_est(get_func_rows(expr->opfuncid));
+ return clamp_row_est(get_function_rows(root, expr->opfuncid, clause));
}
}
return 1.0;
Node *node = (Node *) lfirst(lc);
double itemrows;
- itemrows = expression_returns_set_rows(node);
+ itemrows = expression_returns_set_rows(root, node);
if (tlist_rows < itemrows)
tlist_rows = itemrows;
}
#include "catalog/heap.h"
#include "catalog/partition.h"
#include "catalog/pg_am.h"
+#include "catalog/pg_proc.h"
#include "catalog/pg_statistic_ext.h"
#include "foreign/fdwapi.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
+#include "nodes/supportnodes.h"
#include "optimizer/clauses.h"
#include "optimizer/cost.h"
#include "optimizer/optimizer.h"
* Returns the selectivity of a specified join operator clause.
* This code executes registered procedures stored in the
* operator relation, by calling the function manager.
+ *
+ * See clause_selectivity() for the meaning of the additional parameters.
*/
Selectivity
join_selectivity(PlannerInfo *root,
return (Selectivity) result;
}
+/*
+ * function_selectivity
+ *
+ * Returns the selectivity of a specified boolean function clause.
+ * This code executes registered procedures stored in the
+ * pg_proc relation, by calling the function manager.
+ *
+ * See clause_selectivity() for the meaning of the additional parameters.
+ */
+Selectivity
+function_selectivity(PlannerInfo *root,
+ Oid funcid,
+ List *args,
+ Oid inputcollid,
+ bool is_join,
+ int varRelid,
+ JoinType jointype,
+ SpecialJoinInfo *sjinfo)
+{
+ RegProcedure prosupport = get_func_support(funcid);
+ SupportRequestSelectivity req;
+ SupportRequestSelectivity *sresult;
+
+ /*
+ * If no support function is provided, use our historical default
+ * estimate, 0.3333333. This seems a pretty unprincipled choice, but
+ * Postgres has been using that estimate for function calls since 1992.
+ * The hoariness of this behavior suggests that we should not be in too
+ * much hurry to use another value.
+ */
+ if (!prosupport)
+ return (Selectivity) 0.3333333;
+
+ req.type = T_SupportRequestSelectivity;
+ req.root = root;
+ req.funcid = funcid;
+ req.args = args;
+ req.inputcollid = inputcollid;
+ req.is_join = is_join;
+ req.varRelid = varRelid;
+ req.jointype = jointype;
+ req.sjinfo = sjinfo;
+ req.selectivity = -1; /* to catch failure to set the value */
+
+ sresult = (SupportRequestSelectivity *)
+ DatumGetPointer(OidFunctionCall1(prosupport,
+ PointerGetDatum(&req)));
+
+ /* If support function fails, use default */
+ if (sresult != &req)
+ return (Selectivity) 0.3333333;
+
+ if (req.selectivity < 0.0 || req.selectivity > 1.0)
+ elog(ERROR, "invalid function selectivity: %f", req.selectivity);
+
+ return (Selectivity) req.selectivity;
+}
+
+/*
+ * add_function_cost
+ *
+ * Get an estimate of the execution cost of a function, and *add* it to
+ * the contents of *cost. The estimate may include both one-time and
+ * per-tuple components, since QualCost does.
+ *
+ * The funcid must always be supplied. If it is being called as the
+ * implementation of a specific parsetree node (FuncExpr, OpExpr,
+ * WindowFunc, etc), pass that as "node", else pass NULL.
+ *
+ * In some usages root might be NULL, too.
+ */
+void
+add_function_cost(PlannerInfo *root, Oid funcid, Node *node,
+ QualCost *cost)
+{
+ HeapTuple proctup;
+ Form_pg_proc procform;
+
+ proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
+ if (!HeapTupleIsValid(proctup))
+ elog(ERROR, "cache lookup failed for function %u", funcid);
+ procform = (Form_pg_proc) GETSTRUCT(proctup);
+
+ if (OidIsValid(procform->prosupport))
+ {
+ SupportRequestCost req;
+ SupportRequestCost *sresult;
+
+ req.type = T_SupportRequestCost;
+ req.root = root;
+ req.funcid = funcid;
+ req.node = node;
+
+ /* Initialize cost fields so that support function doesn't have to */
+ req.startup = 0;
+ req.per_tuple = 0;
+
+ sresult = (SupportRequestCost *)
+ DatumGetPointer(OidFunctionCall1(procform->prosupport,
+ PointerGetDatum(&req)));
+
+ if (sresult == &req)
+ {
+ /* Success, so accumulate support function's estimate into *cost */
+ cost->startup += req.startup;
+ cost->per_tuple += req.per_tuple;
+ ReleaseSysCache(proctup);
+ return;
+ }
+ }
+
+ /* No support function, or it failed, so rely on procost */
+ cost->per_tuple += procform->procost * cpu_operator_cost;
+
+ ReleaseSysCache(proctup);
+}
+
+/*
+ * get_function_rows
+ *
+ * Get an estimate of the number of rows returned by a set-returning function.
+ *
+ * The funcid must always be supplied. In current usage, the calling node
+ * will always be supplied, and will be either a FuncExpr or OpExpr.
+ * But it's a good idea to not fail if it's NULL.
+ *
+ * In some usages root might be NULL, too.
+ *
+ * Note: this returns the unfiltered result of the support function, if any.
+ * It's usually a good idea to apply clamp_row_est() to the result, but we
+ * leave it to the caller to do so.
+ */
+double
+get_function_rows(PlannerInfo *root, Oid funcid, Node *node)
+{
+ HeapTuple proctup;
+ Form_pg_proc procform;
+ double result;
+
+ proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
+ if (!HeapTupleIsValid(proctup))
+ elog(ERROR, "cache lookup failed for function %u", funcid);
+ procform = (Form_pg_proc) GETSTRUCT(proctup);
+
+ Assert(procform->proretset); /* else caller error */
+
+ if (OidIsValid(procform->prosupport))
+ {
+ SupportRequestRows req;
+ SupportRequestRows *sresult;
+
+ req.type = T_SupportRequestRows;
+ req.root = root;
+ req.funcid = funcid;
+ req.node = node;
+
+ req.rows = 0; /* just for sanity */
+
+ sresult = (SupportRequestRows *)
+ DatumGetPointer(OidFunctionCall1(procform->prosupport,
+ PointerGetDatum(&req)));
+
+ if (sresult == &req)
+ {
+ /* Success */
+ ReleaseSysCache(proctup);
+ return req.rows;
+ }
+ }
+
+ /* No support function, or it failed, so rely on prorows */
+ result = procform->prorows;
+
+ ReleaseSysCache(proctup);
+
+ return result;
+}
+
/*
* has_unique_index
*
#include "catalog/pg_type.h"
#include "funcapi.h"
#include "libpq/pqformat.h"
+#include "nodes/nodeFuncs.h"
+#include "nodes/supportnodes.h"
+#include "optimizer/optimizer.h"
#include "utils/array.h"
#include "utils/arrayaccess.h"
#include "utils/builtins.h"
#include "utils/datum.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
+#include "utils/selfuncs.h"
#include "utils/typcache.h"
}
}
+/*
+ * Planner support function for array_unnest(anyarray)
+ */
+Datum
+array_unnest_support(PG_FUNCTION_ARGS)
+{
+ Node *rawreq = (Node *) PG_GETARG_POINTER(0);
+ Node *ret = NULL;
+
+ if (IsA(rawreq, SupportRequestRows))
+ {
+ /* Try to estimate the number of rows returned */
+ SupportRequestRows *req = (SupportRequestRows *) rawreq;
+
+ if (is_funcclause(req->node)) /* be paranoid */
+ {
+ List *args = ((FuncExpr *) req->node)->args;
+ Node *arg1;
+
+ /* We can use estimated argument values here */
+ arg1 = estimate_expression_value(req->root, linitial(args));
+
+ req->rows = estimate_array_length(arg1);
+ ret = (Node *) req;
+ }
+ }
+
+ PG_RETURN_POINTER(ret);
+}
+
/*
* array_replace/array_remove support
#include <ctype.h>
#include <limits.h>
+#include <math.h>
#include "catalog/pg_type.h"
#include "common/int.h"
#include "funcapi.h"
#include "libpq/pqformat.h"
+#include "nodes/nodeFuncs.h"
+#include "nodes/supportnodes.h"
+#include "optimizer/optimizer.h"
#include "utils/array.h"
#include "utils/builtins.h"
/* do when there is no more left */
SRF_RETURN_DONE(funcctx);
}
+
+/*
+ * Planner support function for generate_series(int4, int4 [, int4])
+ */
+Datum
+generate_series_int4_support(PG_FUNCTION_ARGS)
+{
+ Node *rawreq = (Node *) PG_GETARG_POINTER(0);
+ Node *ret = NULL;
+
+ if (IsA(rawreq, SupportRequestRows))
+ {
+ /* Try to estimate the number of rows returned */
+ SupportRequestRows *req = (SupportRequestRows *) rawreq;
+
+ if (is_funcclause(req->node)) /* be paranoid */
+ {
+ List *args = ((FuncExpr *) req->node)->args;
+ Node *arg1,
+ *arg2,
+ *arg3;
+
+ /* We can use estimated argument values here */
+ arg1 = estimate_expression_value(req->root, linitial(args));
+ arg2 = estimate_expression_value(req->root, lsecond(args));
+ if (list_length(args) >= 3)
+ arg3 = estimate_expression_value(req->root, lthird(args));
+ else
+ arg3 = NULL;
+
+ /*
+ * If any argument is constant NULL, we can safely assume that
+ * zero rows are returned. Otherwise, if they're all non-NULL
+ * constants, we can calculate the number of rows that will be
+ * returned. Use double arithmetic to avoid overflow hazards.
+ */
+ if ((IsA(arg1, Const) &&
+ ((Const *) arg1)->constisnull) ||
+ (IsA(arg2, Const) &&
+ ((Const *) arg2)->constisnull) ||
+ (arg3 != NULL && IsA(arg3, Const) &&
+ ((Const *) arg3)->constisnull))
+ {
+ req->rows = 0;
+ ret = (Node *) req;
+ }
+ else if (IsA(arg1, Const) &&
+ IsA(arg2, Const) &&
+ (arg3 == NULL || IsA(arg3, Const)))
+ {
+ double start,
+ finish,
+ step;
+
+ start = DatumGetInt32(((Const *) arg1)->constvalue);
+ finish = DatumGetInt32(((Const *) arg2)->constvalue);
+ step = arg3 ? DatumGetInt32(((Const *) arg3)->constvalue) : 1;
+
+ /* This equation works for either sign of step */
+ if (step != 0)
+ {
+ req->rows = floor((finish - start + step) / step);
+ ret = (Node *) req;
+ }
+ }
+ }
+ }
+
+ PG_RETURN_POINTER(ret);
+}
#include "common/int.h"
#include "funcapi.h"
#include "libpq/pqformat.h"
+#include "nodes/nodeFuncs.h"
+#include "nodes/supportnodes.h"
+#include "optimizer/optimizer.h"
#include "utils/int8.h"
#include "utils/builtins.h"
/* do when there is no more left */
SRF_RETURN_DONE(funcctx);
}
+
+/*
+ * Planner support function for generate_series(int8, int8 [, int8])
+ */
+Datum
+generate_series_int8_support(PG_FUNCTION_ARGS)
+{
+ Node *rawreq = (Node *) PG_GETARG_POINTER(0);
+ Node *ret = NULL;
+
+ if (IsA(rawreq, SupportRequestRows))
+ {
+ /* Try to estimate the number of rows returned */
+ SupportRequestRows *req = (SupportRequestRows *) rawreq;
+
+ if (is_funcclause(req->node)) /* be paranoid */
+ {
+ List *args = ((FuncExpr *) req->node)->args;
+ Node *arg1,
+ *arg2,
+ *arg3;
+
+ /* We can use estimated argument values here */
+ arg1 = estimate_expression_value(req->root, linitial(args));
+ arg2 = estimate_expression_value(req->root, lsecond(args));
+ if (list_length(args) >= 3)
+ arg3 = estimate_expression_value(req->root, lthird(args));
+ else
+ arg3 = NULL;
+
+ /*
+ * If any argument is constant NULL, we can safely assume that
+ * zero rows are returned. Otherwise, if they're all non-NULL
+ * constants, we can calculate the number of rows that will be
+ * returned. Use double arithmetic to avoid overflow hazards.
+ */
+ if ((IsA(arg1, Const) &&
+ ((Const *) arg1)->constisnull) ||
+ (IsA(arg2, Const) &&
+ ((Const *) arg2)->constisnull) ||
+ (arg3 != NULL && IsA(arg3, Const) &&
+ ((Const *) arg3)->constisnull))
+ {
+ req->rows = 0;
+ ret = (Node *) req;
+ }
+ else if (IsA(arg1, Const) &&
+ IsA(arg2, Const) &&
+ (arg3 == NULL || IsA(arg3, Const)))
+ {
+ double start,
+ finish,
+ step;
+
+ start = DatumGetInt64(((Const *) arg1)->constvalue);
+ finish = DatumGetInt64(((Const *) arg2)->constvalue);
+ step = arg3 ? DatumGetInt64(((Const *) arg3)->constvalue) : 1;
+
+ /* This equation works for either sign of step */
+ if (step != 0)
+ {
+ req->rows = floor((finish - start + step) / step);
+ ret = (Node *) req;
+ }
+ }
+ }
+ }
+
+ PG_RETURN_POINTER(ret);
+}
selec = var_eq_const(&vardata, BooleanEqualOperator,
BoolGetDatum(true), false, true, false);
}
- else if (is_funcclause(arg))
- {
- /*
- * If we have no stats and it's a function call, estimate 0.3333333.
- * This seems a pretty unprincipled choice, but Postgres has been
- * using that estimate for function calls since 1992. The hoariness
- * of this behavior suggests that we should not be in too much hurry
- * to use another value.
- */
- selec = 0.3333333;
- }
else
{
/* Otherwise, the default estimate is 0.5 */
* pointless to worry too much about this without much better
* estimates for SRF output rowcounts than we have today.)
*/
- this_srf_multiplier = expression_returns_set_rows(groupexpr);
+ this_srf_multiplier = expression_returns_set_rows(root, groupexpr);
if (srf_multiplier < this_srf_multiplier)
srf_multiplier = this_srf_multiplier;
}
/*
- * get_func_cost
- * Given procedure id, return the function's procost field.
- */
-float4
-get_func_cost(Oid funcid)
-{
- HeapTuple tp;
- float4 result;
-
- tp = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
- if (!HeapTupleIsValid(tp))
- elog(ERROR, "cache lookup failed for function %u", funcid);
-
- result = ((Form_pg_proc) GETSTRUCT(tp))->procost;
- ReleaseSysCache(tp);
- return result;
-}
-
-/*
- * get_func_rows
- * Given procedure id, return the function's prorows field.
+ * get_func_support
+ *
+ * Returns the support function OID associated with a given function,
+ * or InvalidOid if there is none.
*/
-float4
-get_func_rows(Oid funcid)
+RegProcedure
+get_func_support(Oid funcid)
{
HeapTuple tp;
- float4 result;
tp = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
- if (!HeapTupleIsValid(tp))
- elog(ERROR, "cache lookup failed for function %u", funcid);
+ if (HeapTupleIsValid(tp))
+ {
+ Form_pg_proc functup = (Form_pg_proc) GETSTRUCT(tp);
+ RegProcedure result;
- result = ((Form_pg_proc) GETSTRUCT(tp))->prorows;
- ReleaseSysCache(tp);
- return result;
+ result = functup->prosupport;
+ ReleaseSysCache(tp);
+ return result;
+ }
+ else
+ return (RegProcedure) InvalidOid;
}
/* ---------- RELATION CACHE ---------- */
*/
/* yyyymmddN */
-#define CATALOG_VERSION_NO 201902091
+#define CATALOG_VERSION_NO 201902092
#endif
proargtypes => 'anyelement _int4 _int4',
prosrc => 'array_fill_with_lower_bounds' },
{ oid => '2331', descr => 'expand array to set of rows',
- proname => 'unnest', prorows => '100', proretset => 't',
- prorettype => 'anyelement', proargtypes => 'anyarray',
+ proname => 'unnest', prorows => '100', prosupport => 'array_unnest_support',
+ proretset => 't', prorettype => 'anyelement', proargtypes => 'anyarray',
prosrc => 'array_unnest' },
+{ oid => '3996', descr => 'planner support for array_unnest',
+ proname => 'array_unnest_support', prorettype => 'internal',
+ proargtypes => 'internal', prosrc => 'array_unnest_support' },
{ oid => '3167',
descr => 'remove any occurrences of an element from an array',
proname => 'array_remove', proisstrict => 'f', prorettype => 'anyarray',
# non-persistent series generator
{ oid => '1066', descr => 'non-persistent series generator',
- proname => 'generate_series', prorows => '1000', proretset => 't',
+ proname => 'generate_series', prorows => '1000',
+ prosupport => 'generate_series_int4_support', proretset => 't',
prorettype => 'int4', proargtypes => 'int4 int4 int4',
prosrc => 'generate_series_step_int4' },
{ oid => '1067', descr => 'non-persistent series generator',
- proname => 'generate_series', prorows => '1000', proretset => 't',
+ proname => 'generate_series', prorows => '1000',
+ prosupport => 'generate_series_int4_support', proretset => 't',
prorettype => 'int4', proargtypes => 'int4 int4',
prosrc => 'generate_series_int4' },
+{ oid => '3994', descr => 'planner support for generate_series',
+ proname => 'generate_series_int4_support', prorettype => 'internal',
+ proargtypes => 'internal', prosrc => 'generate_series_int4_support' },
{ oid => '1068', descr => 'non-persistent series generator',
- proname => 'generate_series', prorows => '1000', proretset => 't',
+ proname => 'generate_series', prorows => '1000',
+ prosupport => 'generate_series_int8_support', proretset => 't',
prorettype => 'int8', proargtypes => 'int8 int8 int8',
prosrc => 'generate_series_step_int8' },
{ oid => '1069', descr => 'non-persistent series generator',
- proname => 'generate_series', prorows => '1000', proretset => 't',
+ proname => 'generate_series', prorows => '1000',
+ prosupport => 'generate_series_int8_support', proretset => 't',
prorettype => 'int8', proargtypes => 'int8 int8',
prosrc => 'generate_series_int8' },
+{ oid => '3995', descr => 'planner support for generate_series',
+ proname => 'generate_series_int8_support', prorettype => 'internal',
+ proargtypes => 'internal', prosrc => 'generate_series_int8_support' },
{ oid => '3259', descr => 'non-persistent series generator',
proname => 'generate_series', prorows => '1000', proretset => 't',
prorettype => 'numeric', proargtypes => 'numeric numeric numeric',
T_TsmRoutine, /* in access/tsmapi.h */
T_ForeignKeyCacheInfo, /* in utils/rel.h */
T_CallContext, /* in nodes/parsenodes.h */
- T_SupportRequestSimplify /* in nodes/supportnodes.h */
+ T_SupportRequestSimplify, /* in nodes/supportnodes.h */
+ T_SupportRequestSelectivity, /* in nodes/supportnodes.h */
+ T_SupportRequestCost, /* in nodes/supportnodes.h */
+ T_SupportRequestRows /* in nodes/supportnodes.h */
} NodeTag;
/*
bool hasNonPartial; /* does any agg not support partial mode? */
bool hasNonSerial; /* is any partial agg non-serializable? */
QualCost transCost; /* total per-input-row execution costs */
- Cost finalCost; /* total per-aggregated-row costs */
+ QualCost finalCost; /* total per-aggregated-row costs */
Size transitionSpace; /* space for pass-by-ref transition data */
} AggClauseCosts;
#include "nodes/primnodes.h"
struct PlannerInfo; /* avoid including relation.h here */
+struct SpecialJoinInfo;
/*
FuncExpr *fcall; /* Function call to be simplified */
} SupportRequestSimplify;
+/*
+ * The Selectivity request allows the support function to provide a
+ * selectivity estimate for a function appearing at top level of a WHERE
+ * clause (so it applies only to functions returning boolean).
+ *
+ * The input arguments are the same as are supplied to operator restriction
+ * and join estimators, except that we unify those two APIs into just one
+ * request type. See clause_selectivity() for the details.
+ *
+ * If an estimate can be made, store it into the "selectivity" field and
+ * return the address of the SupportRequestSelectivity node; the estimate
+ * must be between 0 and 1 inclusive. Return NULL if no estimate can be
+ * made (in which case the planner will fall back to a default estimate,
+ * traditionally 1/3).
+ *
+ * If the target function is being used as the implementation of an operator,
+ * the support function will not be used for this purpose; the operator's
+ * restriction or join estimator is consulted instead.
+ */
+typedef struct SupportRequestSelectivity
+{
+ NodeTag type;
+
+ /* Input fields: */
+ struct PlannerInfo *root; /* Planner's infrastructure */
+ Oid funcid; /* function we are inquiring about */
+ List *args; /* pre-simplified arguments to function */
+ Oid inputcollid; /* function's input collation */
+ bool is_join; /* is this a join or restriction case? */
+ int varRelid; /* if restriction, RTI of target relation */
+ JoinType jointype; /* if join, outer join type */
+ struct SpecialJoinInfo *sjinfo; /* if outer join, info about join */
+
+ /* Output fields: */
+ Selectivity selectivity; /* returned selectivity estimate */
+} SupportRequestSelectivity;
+
+/*
+ * The Cost request allows the support function to provide an execution
+ * cost estimate for its target function. The cost estimate can include
+ * both a one-time (query startup) component and a per-execution component.
+ * The estimate should *not* include the costs of evaluating the target
+ * function's arguments, only the target function itself.
+ *
+ * The "node" argument is normally the parse node that is invoking the
+ * target function. This is a FuncExpr in the simplest case, but it could
+ * also be an OpExpr, DistinctExpr, NullIfExpr, or WindowFunc, or possibly
+ * other cases in future. NULL is passed if the function cannot presume
+ * its arguments to be equivalent to what the calling node presents as
+ * arguments; that happens for, e.g., aggregate support functions and
+ * per-column comparison operators used by RowExprs.
+ *
+ * If an estimate can be made, store it into the cost fields and return the
+ * address of the SupportRequestCost node. Return NULL if no estimate can be
+ * made, in which case the planner will rely on the target function's procost
+ * field. (Note: while procost is automatically scaled by cpu_operator_cost,
+ * this is not the case for the outputs of the Cost request; the support
+ * function must scale its results appropriately on its own.)
+ */
+typedef struct SupportRequestCost
+{
+ NodeTag type;
+
+ /* Input fields: */
+ struct PlannerInfo *root; /* Planner's infrastructure (could be NULL) */
+ Oid funcid; /* function we are inquiring about */
+ Node *node; /* parse node invoking function, or NULL */
+
+ /* Output fields: */
+ Cost startup; /* one-time cost */
+ Cost per_tuple; /* per-evaluation cost */
+} SupportRequestCost;
+
+/*
+ * The Rows request allows the support function to provide an output rowcount
+ * estimate for its target function (so it applies only to set-returning
+ * functions).
+ *
+ * The "node" argument is the parse node that is invoking the target function;
+ * currently this will always be a FuncExpr or OpExpr.
+ *
+ * If an estimate can be made, store it into the rows field and return the
+ * address of the SupportRequestRows node. Return NULL if no estimate can be
+ * made, in which case the planner will rely on the target function's prorows
+ * field.
+ */
+typedef struct SupportRequestRows
+{
+ NodeTag type;
+
+ /* Input fields: */
+ struct PlannerInfo *root; /* Planner's infrastructure (could be NULL) */
+ Oid funcid; /* function we are inquiring about */
+ Node *node; /* parse node invoking function */
+
+ /* Output fields: */
+ double rows; /* number of rows expected to be returned */
+} SupportRequestRows;
+
#endif /* SUPPORTNODES_H */
extern bool contain_window_function(Node *clause);
extern WindowFuncLists *find_window_functions(Node *clause, Index maxWinRef);
-extern double expression_returns_set_rows(Node *clause);
+extern double expression_returns_set_rows(PlannerInfo *root, Node *clause);
extern bool contain_subplans(Node *clause);
JoinType jointype,
SpecialJoinInfo *sjinfo);
+extern Selectivity function_selectivity(PlannerInfo *root,
+ Oid funcid,
+ List *args,
+ Oid inputcollid,
+ bool is_join,
+ int varRelid,
+ JoinType jointype,
+ SpecialJoinInfo *sjinfo);
+
+extern void add_function_cost(PlannerInfo *root, Oid funcid, Node *node,
+ QualCost *cost);
+
+extern double get_function_rows(PlannerInfo *root, Oid funcid, Node *node);
+
extern bool has_row_triggers(PlannerInfo *root, Index rti, CmdType event);
#endif /* PLANCAT_H */
extern char func_parallel(Oid funcid);
extern char get_func_prokind(Oid funcid);
extern bool get_func_leakproof(Oid funcid);
-extern float4 get_func_cost(Oid funcid);
-extern float4 get_func_rows(Oid funcid);
+extern RegProcedure get_func_support(Oid funcid);
extern Oid get_relname_relid(const char *relname, Oid relnamespace);
extern char *get_rel_name(Oid relid);
extern Oid get_rel_namespace(Oid relid);
LINE 1: SELECT num_nulls();
^
HINT: No function matches the given name and argument types. You might need to add explicit type casts.
+--
+-- Test adding a support function to a subject function
+--
+CREATE FUNCTION my_int_eq(int, int) RETURNS bool
+ LANGUAGE internal STRICT IMMUTABLE PARALLEL SAFE
+ AS $$int4eq$$;
+-- By default, planner does not think that's selective
+EXPLAIN (COSTS OFF)
+SELECT * FROM tenk1 a JOIN tenk1 b ON a.unique1 = b.unique1
+WHERE my_int_eq(a.unique2, 42);
+ QUERY PLAN
+----------------------------------------------
+ Hash Join
+ Hash Cond: (b.unique1 = a.unique1)
+ -> Seq Scan on tenk1 b
+ -> Hash
+ -> Seq Scan on tenk1 a
+ Filter: my_int_eq(unique2, 42)
+(6 rows)
+
+-- With support function that knows it's int4eq, we get a different plan
+ALTER FUNCTION my_int_eq(int, int) SUPPORT test_support_func;
+EXPLAIN (COSTS OFF)
+SELECT * FROM tenk1 a JOIN tenk1 b ON a.unique1 = b.unique1
+WHERE my_int_eq(a.unique2, 42);
+ QUERY PLAN
+-------------------------------------------------
+ Nested Loop
+ -> Seq Scan on tenk1 a
+ Filter: my_int_eq(unique2, 42)
+ -> Index Scan using tenk1_unique1 on tenk1 b
+ Index Cond: (unique1 = a.unique1)
+(5 rows)
+
+-- Also test non-default rowcount estimate
+CREATE FUNCTION my_gen_series(int, int) RETURNS SETOF integer
+ LANGUAGE internal STRICT IMMUTABLE PARALLEL SAFE
+ AS $$generate_series_int4$$
+ SUPPORT test_support_func;
+EXPLAIN (COSTS OFF)
+SELECT * FROM tenk1 a JOIN my_gen_series(1,1000) g ON a.unique1 = g;
+ QUERY PLAN
+----------------------------------------
+ Hash Join
+ Hash Cond: (g.g = a.unique1)
+ -> Function Scan on my_gen_series g
+ -> Hash
+ -> Seq Scan on tenk1 a
+(5 rows)
+
+EXPLAIN (COSTS OFF)
+SELECT * FROM tenk1 a JOIN my_gen_series(1,10) g ON a.unique1 = g;
+ QUERY PLAN
+-------------------------------------------------
+ Nested Loop
+ -> Function Scan on my_gen_series g
+ -> Index Scan using tenk1_unique1 on tenk1 a
+ Index Cond: (unique1 = g.g)
+(4 rows)
+
--
explain (verbose, costs off)
select * from int4_tbl o where (f1, f1) in
- (select f1, generate_series(1,2) / 10 g from int4_tbl i group by f1);
+ (select f1, generate_series(1,50) / 10 g from int4_tbl i group by f1);
QUERY PLAN
-------------------------------------------------------------------
Nested Loop Semi Join
Output: "ANY_subquery".f1, "ANY_subquery".g
Filter: ("ANY_subquery".f1 = "ANY_subquery".g)
-> Result
- Output: i.f1, ((generate_series(1, 2)) / 10)
+ Output: i.f1, ((generate_series(1, 50)) / 10)
-> ProjectSet
- Output: generate_series(1, 2), i.f1
+ Output: generate_series(1, 50), i.f1
-> HashAggregate
Output: i.f1
Group Key: i.f1
(19 rows)
select * from int4_tbl o where (f1, f1) in
- (select f1, generate_series(1,2) / 10 g from int4_tbl i group by f1);
+ (select f1, generate_series(1,50) / 10 g from int4_tbl i group by f1);
f1
----
0
AS '@libdir@/regress@DLSUFFIX@', 'test_fdw_handler'
LANGUAGE C;
+CREATE FUNCTION test_support_func(internal)
+ RETURNS internal
+ AS '@libdir@/regress@DLSUFFIX@', 'test_support_func'
+ LANGUAGE C STRICT;
+
-- Things that shouldn't work:
CREATE FUNCTION test1 (int) RETURNS int LANGUAGE SQL
RETURNS fdw_handler
AS '@libdir@/regress@DLSUFFIX@', 'test_fdw_handler'
LANGUAGE C;
+CREATE FUNCTION test_support_func(internal)
+ RETURNS internal
+ AS '@libdir@/regress@DLSUFFIX@', 'test_support_func'
+ LANGUAGE C STRICT;
-- Things that shouldn't work:
CREATE FUNCTION test1 (int) RETURNS int LANGUAGE SQL
AS 'SELECT ''not an integer'';';
#include "access/transam.h"
#include "access/tuptoaster.h"
#include "access/xact.h"
+#include "catalog/pg_operator.h"
#include "catalog/pg_type.h"
#include "commands/sequence.h"
#include "commands/trigger.h"
#include "executor/executor.h"
#include "executor/spi.h"
#include "miscadmin.h"
+#include "nodes/supportnodes.h"
+#include "optimizer/optimizer.h"
+#include "optimizer/plancat.h"
#include "port/atomics.h"
#include "utils/builtins.h"
#include "utils/geo_decls.h"
elog(ERROR, "test_fdw_handler is not implemented");
PG_RETURN_NULL();
}
+
+PG_FUNCTION_INFO_V1(test_support_func);
+Datum
+test_support_func(PG_FUNCTION_ARGS)
+{
+ Node *rawreq = (Node *) PG_GETARG_POINTER(0);
+ Node *ret = NULL;
+
+ if (IsA(rawreq, SupportRequestSelectivity))
+ {
+ /*
+ * Assume that the target is int4eq; that's safe as long as we don't
+ * attach this to any other boolean-returning function.
+ */
+ SupportRequestSelectivity *req = (SupportRequestSelectivity *) rawreq;
+ Selectivity s1;
+
+ if (req->is_join)
+ s1 = join_selectivity(req->root, Int4EqualOperator,
+ req->args,
+ req->inputcollid,
+ req->jointype,
+ req->sjinfo);
+ else
+ s1 = restriction_selectivity(req->root, Int4EqualOperator,
+ req->args,
+ req->inputcollid,
+ req->varRelid);
+
+ req->selectivity = s1;
+ ret = (Node *) req;
+ }
+
+ if (IsA(rawreq, SupportRequestCost))
+ {
+ /* Provide some generic estimate */
+ SupportRequestCost *req = (SupportRequestCost *) rawreq;
+
+ req->startup = 0;
+ req->per_tuple = 2 * cpu_operator_cost;
+ ret = (Node *) req;
+ }
+
+ if (IsA(rawreq, SupportRequestRows))
+ {
+ /*
+ * Assume that the target is generate_series_int4; that's safe as long
+ * as we don't attach this to any other set-returning function.
+ */
+ SupportRequestRows *req = (SupportRequestRows *) rawreq;
+
+ if (req->node && IsA(req->node, FuncExpr)) /* be paranoid */
+ {
+ List *args = ((FuncExpr *) req->node)->args;
+ Node *arg1 = linitial(args);
+ Node *arg2 = lsecond(args);
+
+ if (IsA(arg1, Const) &&
+ !((Const *) arg1)->constisnull &&
+ IsA(arg2, Const) &&
+ !((Const *) arg2)->constisnull)
+ {
+ int32 val1 = DatumGetInt32(((Const *) arg1)->constvalue);
+ int32 val2 = DatumGetInt32(((Const *) arg2)->constvalue);
+
+ req->rows = val2 - val1 + 1;
+ ret = (Node *) req;
+ }
+ }
+ }
+
+ PG_RETURN_POINTER(ret);
+}
-- should fail, one or more arguments is required
SELECT num_nonnulls();
SELECT num_nulls();
+
+--
+-- Test adding a support function to a subject function
+--
+
+CREATE FUNCTION my_int_eq(int, int) RETURNS bool
+ LANGUAGE internal STRICT IMMUTABLE PARALLEL SAFE
+ AS $$int4eq$$;
+
+-- By default, planner does not think that's selective
+EXPLAIN (COSTS OFF)
+SELECT * FROM tenk1 a JOIN tenk1 b ON a.unique1 = b.unique1
+WHERE my_int_eq(a.unique2, 42);
+
+-- With support function that knows it's int4eq, we get a different plan
+ALTER FUNCTION my_int_eq(int, int) SUPPORT test_support_func;
+
+EXPLAIN (COSTS OFF)
+SELECT * FROM tenk1 a JOIN tenk1 b ON a.unique1 = b.unique1
+WHERE my_int_eq(a.unique2, 42);
+
+-- Also test non-default rowcount estimate
+CREATE FUNCTION my_gen_series(int, int) RETURNS SETOF integer
+ LANGUAGE internal STRICT IMMUTABLE PARALLEL SAFE
+ AS $$generate_series_int4$$
+ SUPPORT test_support_func;
+
+EXPLAIN (COSTS OFF)
+SELECT * FROM tenk1 a JOIN my_gen_series(1,1000) g ON a.unique1 = g;
+
+EXPLAIN (COSTS OFF)
+SELECT * FROM tenk1 a JOIN my_gen_series(1,10) g ON a.unique1 = g;
--
explain (verbose, costs off)
select * from int4_tbl o where (f1, f1) in
- (select f1, generate_series(1,2) / 10 g from int4_tbl i group by f1);
+ (select f1, generate_series(1,50) / 10 g from int4_tbl i group by f1);
select * from int4_tbl o where (f1, f1) in
- (select f1, generate_series(1,2) / 10 g from int4_tbl i group by f1);
+ (select f1, generate_series(1,50) / 10 g from int4_tbl i group by f1);
--
-- check for over-optimization of whole-row Var referencing an Append plan
projects / postgresql / commitdiff