* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.422 2009/02/02 19:31:39 alvherre Exp $
+ * $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.423 2009/02/06 23:43:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/* EquivalenceClasses are never copied, so shallow-copy the pointers */
COPY_SCALAR_FIELD(parent_ec);
COPY_SCALAR_FIELD(eval_cost);
- COPY_SCALAR_FIELD(this_selec);
+ COPY_SCALAR_FIELD(norm_selec);
+ COPY_SCALAR_FIELD(outer_selec);
COPY_NODE_FIELD(mergeopfamilies);
/* EquivalenceClasses are never copied, so shallow-copy the pointers */
COPY_SCALAR_FIELD(left_ec);
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.351 2009/02/02 19:31:39 alvherre Exp $
+ * $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.352 2009/02/06 23:43:23 tgl Exp $
*
* NOTES
* Every node type that can appear in stored rules' parsetrees *must*
WRITE_BITMAPSET_FIELD(right_relids);
WRITE_NODE_FIELD(orclause);
/* don't write parent_ec, leads to infinite recursion in plan tree dump */
- WRITE_FLOAT_FIELD(this_selec, "%.4f");
+ WRITE_FLOAT_FIELD(norm_selec, "%.4f");
+ WRITE_FLOAT_FIELD(outer_selec, "%.4f");
WRITE_NODE_FIELD(mergeopfamilies);
/* don't write left_ec, leads to infinite recursion in plan tree dump */
/* don't write right_ec, leads to infinite recursion in plan tree dump */
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/optimizer/path/clausesel.c,v 1.96 2009/01/01 17:23:43 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/path/clausesel.c,v 1.97 2009/02/06 23:43:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/*
* If the clause is marked redundant, always return 1.0.
*/
- if (rinfo->this_selec > 1)
+ if (rinfo->norm_selec > 1)
return (Selectivity) 1.0;
/*
* If possible, cache the result of the selectivity calculation for
* the clause. We can cache if varRelid is zero or the clause
* contains only vars of that relid --- otherwise varRelid will affect
- * the result, so mustn't cache.
+ * the result, so mustn't cache. Outer join quals might be examined
+ * with either their join's actual jointype or JOIN_INNER, so we need
+ * two cache variables to remember both cases. Note: we assume the
+ * result won't change if we are switching the input relations or
+ * considering a unique-ified case, so we only need one cache variable
+ * for all non-JOIN_INNER cases.
*/
if (varRelid == 0 ||
bms_is_subset_singleton(rinfo->clause_relids, varRelid))
{
/* Cacheable --- do we already have the result? */
- if (rinfo->this_selec >= 0)
- return rinfo->this_selec;
+ if (jointype == JOIN_INNER)
+ {
+ if (rinfo->norm_selec >= 0)
+ return rinfo->norm_selec;
+ }
+ else
+ {
+ if (rinfo->outer_selec >= 0)
+ return rinfo->outer_selec;
+ }
cacheable = true;
}
/* Cache the result if possible */
if (cacheable)
- rinfo->this_selec = s1;
+ {
+ if (jointype == JOIN_INNER)
+ rinfo->norm_selec = s1;
+ else
+ rinfo->outer_selec = s1;
+ }
#ifdef SELECTIVITY_DEBUG
elog(DEBUG4, "clause_selectivity: s1 %f", s1);
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.203 2009/01/01 17:23:43 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.204 2009/02/06 23:43:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
PathKey *pathkey);
static bool cost_qual_eval_walker(Node *node, cost_qual_eval_context *context);
static double approx_tuple_count(PlannerInfo *root, JoinPath *path,
- List *quals, SpecialJoinInfo *sjinfo);
+ List *quals);
static void set_rel_width(PlannerInfo *root, RelOptInfo *rel);
static double relation_byte_size(double tuples, int width);
static double page_size(double tuples, int width);
/*
* Get approx # tuples passing the mergequals. We use approx_tuple_count
- * here for speed --- in most cases, any errors won't affect the result
- * much.
+ * here because we need an estimate done with JOIN_INNER semantics.
*/
- mergejointuples = approx_tuple_count(root, &path->jpath,
- mergeclauses, sjinfo);
+ mergejointuples = approx_tuple_count(root, &path->jpath, mergeclauses);
/*
* When there are equal merge keys in the outer relation, the mergejoin
* when we should not. Can we do better without expensive selectivity
* computations?
*
- * For SEMI and ANTI joins, only one inner tuple need be rescanned for
- * each group of same-keyed outer tuples (assuming that all joinquals
- * are merge quals). This makes the effect small enough to ignore,
- * so we just set rescannedtuples = 0. Likewise, the whole issue is
- * moot if we are working from a unique-ified outer input.
+ * The whole issue is moot if we are working from a unique-ified outer
+ * input.
*/
- if (sjinfo->jointype == JOIN_SEMI ||
- sjinfo->jointype == JOIN_ANTI)
- rescannedtuples = 0;
- else if (IsA(outer_path, UniquePath))
+ if (IsA(outer_path, UniquePath))
rescannedtuples = 0;
else
{
/*
* Get approx # tuples passing the hashquals. We use approx_tuple_count
- * here for speed --- in most cases, any errors won't affect the result
- * much.
+ * here because we need an estimate done with JOIN_INNER semantics.
*/
- hashjointuples = approx_tuple_count(root, &path->jpath,
- hashclauses, sjinfo);
+ hashjointuples = approx_tuple_count(root, &path->jpath, hashclauses);
/* cost of source data */
startup_cost += outer_path->startup_cost;
* The quals can be either an implicitly-ANDed list of boolean expressions,
* or a list of RestrictInfo nodes (typically the latter).
*
+ * We intentionally compute the selectivity under JOIN_INNER rules, even
+ * if it's some type of outer join. This is appropriate because we are
+ * trying to figure out how many tuples pass the initial merge or hash
+ * join step.
+ *
* This is quick-and-dirty because we bypass clauselist_selectivity, and
* simply multiply the independent clause selectivities together. Now
* clauselist_selectivity often can't do any better than that anyhow, but
* seems OK to live with the approximation.
*/
static double
-approx_tuple_count(PlannerInfo *root, JoinPath *path,
- List *quals, SpecialJoinInfo *sjinfo)
+approx_tuple_count(PlannerInfo *root, JoinPath *path, List *quals)
{
double tuples;
double outer_tuples = path->outerjoinpath->parent->rows;
double inner_tuples = path->innerjoinpath->parent->rows;
+ SpecialJoinInfo sjinfo;
Selectivity selec = 1.0;
ListCell *l;
+ /*
+ * Make up a SpecialJoinInfo for JOIN_INNER semantics.
+ */
+ sjinfo.type = T_SpecialJoinInfo;
+ sjinfo.min_lefthand = path->outerjoinpath->parent->relids;
+ sjinfo.min_righthand = path->innerjoinpath->parent->relids;
+ sjinfo.syn_lefthand = path->outerjoinpath->parent->relids;
+ sjinfo.syn_righthand = path->innerjoinpath->parent->relids;
+ sjinfo.jointype = JOIN_INNER;
+ /* we don't bother trying to make the remaining fields valid */
+ sjinfo.lhs_strict = false;
+ sjinfo.delay_upper_joins = false;
+ sjinfo.join_quals = NIL;
+
/* Get the approximate selectivity */
foreach(l, quals)
{
Node *qual = (Node *) lfirst(l);
/* Note that clause_selectivity will be able to cache its result */
- selec *= clause_selectivity(root, qual, 0, sjinfo->jointype, sjinfo);
+ selec *= clause_selectivity(root, qual, 0, JOIN_INNER, &sjinfo);
}
- /* Apply it correctly using the input relation sizes */
- if (sjinfo->jointype == JOIN_SEMI)
- tuples = selec * outer_tuples;
- else if (sjinfo->jointype == JOIN_ANTI)
- tuples = (1.0 - selec) * outer_tuples;
- else
- tuples = selec * outer_tuples * inner_tuples;
+ /* Apply it to the input relation sizes */
+ tuples = selec * outer_tuples * inner_tuples;
return clamp_row_est(tuples);
}
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/optimizer/path/equivclass.c,v 1.16 2009/01/01 17:23:43 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/path/equivclass.c,v 1.17 2009/02/06 23:43:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
list_delete_cell(root->left_join_clauses, cell, prev);
/* we throw it back anyway (see notes above) */
/* but the thrown-back clause has no extra selectivity */
- rinfo->this_selec = 2.0;
+ rinfo->norm_selec = 2.0;
+ rinfo->outer_selec = 1.0;
distribute_restrictinfo_to_rels(root, rinfo);
}
else
list_delete_cell(root->right_join_clauses, cell, prev);
/* we throw it back anyway (see notes above) */
/* but the thrown-back clause has no extra selectivity */
- rinfo->this_selec = 2.0;
+ rinfo->norm_selec = 2.0;
+ rinfo->outer_selec = 1.0;
distribute_restrictinfo_to_rels(root, rinfo);
}
else
list_delete_cell(root->full_join_clauses, cell, prev);
/* we throw it back anyway (see notes above) */
/* but the thrown-back clause has no extra selectivity */
- rinfo->this_selec = 2.0;
+ rinfo->norm_selec = 2.0;
+ rinfo->outer_selec = 1.0;
distribute_restrictinfo_to_rels(root, rinfo);
}
else
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/optimizer/path/orindxpath.c,v 1.86 2009/01/01 17:23:44 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/path/orindxpath.c,v 1.87 2009/02/06 23:43:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
{
orig_selec = clause_selectivity(root, (Node *) bestrinfo,
0, JOIN_INNER, NULL);
- bestrinfo->this_selec = orig_selec / or_selec;
+ bestrinfo->norm_selec = orig_selec / or_selec;
/* clamp result to sane range */
- if (bestrinfo->this_selec > 1)
- bestrinfo->this_selec = 1;
+ if (bestrinfo->norm_selec > 1)
+ bestrinfo->norm_selec = 1;
+ /* It isn't an outer join clause, so no need to adjust outer_selec */
}
/* Tell caller to recompute rel's rows estimate */
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/optimizer/prep/prepunion.c,v 1.164 2009/01/01 17:23:44 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/prep/prepunion.c,v 1.165 2009/02/06 23:43:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
* different values when considering the child relation.
*/
newinfo->eval_cost.startup = -1;
- newinfo->this_selec = -1;
+ newinfo->norm_selec = -1;
+ newinfo->outer_selec = -1;
newinfo->left_ec = NULL;
newinfo->right_ec = NULL;
newinfo->left_em = NULL;
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/optimizer/util/restrictinfo.c,v 1.56 2009/01/01 17:23:45 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/util/restrictinfo.c,v 1.57 2009/02/06 23:43:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
restrictinfo->parent_ec = NULL;
restrictinfo->eval_cost.startup = -1;
- restrictinfo->this_selec = -1;
+ restrictinfo->norm_selec = -1;
+ restrictinfo->outer_selec = -1;
restrictinfo->mergeopfamilies = NIL;
* Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/nodes/relation.h,v 1.167 2009/01/01 17:24:00 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/nodes/relation.h,v 1.168 2009/02/06 23:43:24 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/* cache space for cost and selectivity */
QualCost eval_cost; /* eval cost of clause; -1 if not yet set */
- Selectivity this_selec; /* selectivity; -1 if not yet set; >1 means
+ Selectivity norm_selec; /* selectivity for "normal" (JOIN_INNER)
+ * semantics; -1 if not yet set; >1 means
* a redundant clause */
+ Selectivity outer_selec; /* selectivity for outer join semantics;
+ * -1 if not yet set */
/* valid if clause is mergejoinable, else NIL */
List *mergeopfamilies; /* opfamilies containing clause operator */
projects / postgresql / commitdiff