Extract restriction OR clauses whether or not they are indexable
This commit is contained in:
3
.gitignore
vendored
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3
.gitignore
vendored
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@ -0,0 +1,3 @@
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/.gitee/
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/.vscode/
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/.idea/
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@ -20,11 +20,11 @@ endif
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ifeq ($(enable_multiple_nodes), yes)
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OBJS = allpaths.o clausesel.o costsize.o equivclass.o indxpath.o \
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joinpath.o joinrels.o orindxpath.o pathkeys.o tidpath.o streampath_base.o \
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joinpath.o joinrels.o pathkeys.o tidpath.o streampath_base.o \
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es_selectivity.o
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else
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OBJS = allpaths.o clausesel.o costsize.o equivclass.o indxpath.o \
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joinpath.o joinrels.o orindxpath.o pathkeys.o tidpath.o \
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joinpath.o joinrels.o pathkeys.o tidpath.o \
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pgxcpath_single.o streampath_single.o streampath_base.o es_selectivity.o
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endif
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@ -819,16 +819,6 @@ static void set_plain_rel_size(PlannerInfo* root, RelOptInfo* rel, RangeTblEntry
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if (rte->tablesample == NULL) {
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/* Mark rel with estimated output rows, width, etc */
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set_baserel_size_estimates(root, rel);
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/*
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* Check to see if we can extract any restriction conditions from join
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* quals that are OR-of-AND structures. If so, add them to the rel's
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* restriction list, and redo the above steps.
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*/
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if (create_or_index_quals(root, rel)) {
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check_partial_indexes(root, rel);
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set_baserel_size_estimates(root, rel);
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}
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} else {
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/* Sampled relation */
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set_tablesample_rel_size(root, rel, rte);
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@ -1494,7 +1494,8 @@ static Path* choose_bitmap_and(PlannerInfo* root, RelOptInfo* rel, List* paths,
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* we can remove this limitation. (But note that this also defends
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* against flat-out duplicate input paths, which can happen because
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* match_join_clauses_to_index will find the same OR join clauses that
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* create_or_index_quals has pulled OR restriction clauses out of.)
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* extract_restriction_or_clauses has pulled OR restriction clauses out
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* of.)
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*
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* For the same reason, we reject AND combinations in which an index
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* predicate clause duplicates another clause. Here we find it necessary
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@ -1,180 +0,0 @@
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/* -------------------------------------------------------------------------
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*
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* orindxpath.cpp
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* Routines to find index paths that match a set of OR clauses
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*
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* Portions Copyright (c) 2020 Huawei Technologies Co.,Ltd.
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* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* src/gausskernel/optimizer/path/orindxpath.cpp
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*
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* -------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "knl/knl_variable.h"
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#include "optimizer/cost.h"
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#include "optimizer/paths.h"
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#include "optimizer/restrictinfo.h"
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/* ----------
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* create_or_index_quals
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* Examine join OR-of-AND quals to see if any useful restriction OR
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* clauses can be extracted. If so, add them to the query.
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*
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* Although a join clause must reference other relations overall,
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* an OR of ANDs clause might contain sub-clauses that reference just this
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* relation and can be used to build a restriction clause.
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* For example consider
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* WHERE ((a.x = 42 AND b.y = 43) OR (a.x = 44 AND b.z = 45));
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* We can transform this into
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* WHERE ((a.x = 42 AND b.y = 43) OR (a.x = 44 AND b.z = 45))
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* AND (a.x = 42 OR a.x = 44)
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* AND (b.y = 43 OR b.z = 45);
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* which opens the potential to build OR indexscans on a and b. In essence
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* this is a partial transformation to CNF (AND of ORs format). It is not
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* complete, however, because we do not unravel the original OR --- doing so
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* would usually bloat the qualification expression to little gain.
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*
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* The added quals are partially redundant with the original OR, and therefore
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* will cause the size of the joinrel to be underestimated when it is finally
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* formed. (This would be true of a full transformation to CNF as well; the
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* fault is not really in the transformation, but in clauselist_selectivity's
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* inability to recognize redundant conditions.) To minimize the collateral
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* damage, we want to minimize the number of quals added. Therefore we do
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* not add every possible extracted restriction condition to the query.
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* Instead, we search for the single restriction condition that generates
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* the most useful (cheapest) OR indexscan, and add only that condition.
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* This is a pretty ad-hoc heuristic, but quite useful.
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*
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* We can then compensate for the redundancy of the added qual by poking
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* the recorded selectivity of the original OR clause, thereby ensuring
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* the added qual doesn't change the estimated size of the joinrel when
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* it is finally formed. This is a MAJOR HACK: it depends on the fact
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* that clause selectivities are cached and on the fact that the same
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* RestrictInfo node will appear in every joininfo list that might be used
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* when the joinrel is formed. And it probably isn't right in cases where
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* the size estimation is nonlinear (i.e., outer and IN joins). But it
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* beats not doing anything.
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*
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* NOTE: one might think this messiness could be worked around by generating
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* the indexscan path with a small path->rows value, and not touching the
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* rel's baserestrictinfo or rel->rows. However, that does not work.
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* The optimizer's fundamental design assumes that every general-purpose
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* Path for a given relation generates the same number of rows. Without
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* this assumption we'd not be able to optimize solely on the cost of Paths,
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* but would have to take number of output rows into account as well.
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* (The parameterized-paths stuff almost fixes this, but not quite...)
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*
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* 'rel' is the relation entry for which quals are to be created
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*
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* If successful, adds qual(s) to rel->baserestrictinfo and returns TRUE.
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* If no quals available, returns FALSE and doesn't change rel.
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*
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* Note: check_partial_indexes() must have been run previously.
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* ----------
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*/
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bool create_or_index_quals(PlannerInfo* root, RelOptInfo* rel)
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{
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BitmapOrPath* bestpath = NULL;
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RestrictInfo* bestrinfo = NULL;
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List* newrinfos = NIL;
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RestrictInfo* or_rinfo = NULL;
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Selectivity or_selec, orig_selec;
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ListCell* i = NULL;
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/* Skip the whole mess if no indexes */
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if (rel->indexlist == NIL)
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return false;
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/*
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* Find potentially interesting OR joinclauses. We can use any joinclause
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* that is considered safe to move to this rel by the parameterized-path
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* machinery, even though what we are going to do with it is not exactly a
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* parameterized path.
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*/
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foreach (i, rel->joininfo) {
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RestrictInfo* rinfo = (RestrictInfo*)lfirst(i);
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if (restriction_is_or_clause(rinfo) && join_clause_is_movable_to(rinfo, rel->relid)) {
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/*
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* Use the generate_bitmap_or_paths() machinery to estimate the
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* value of each OR clause. We can use regular restriction
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* clauses along with the OR clause contents to generate
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* indexquals. We pass restriction_only = true so that any
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* sub-clauses that are actually joins will be ignored.
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*/
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List* orpaths = NIL;
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ListCell* k = NULL;
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orpaths = generate_bitmap_or_paths(root, rel, list_make1(rinfo), rel->baserestrictinfo, true);
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if (rel->isPartitionedTable) {
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orpaths = list_concat(
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orpaths, GenerateBitmapOrPathsUseGPI(root, rel, list_make1(rinfo), rel->baserestrictinfo, true));
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}
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/* Locate the cheapest OR path */
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foreach (k, orpaths) {
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BitmapOrPath* path = (BitmapOrPath*)lfirst(k);
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AssertEreport(IsA(path, BitmapOrPath), MOD_OPT, "Restriction information is incorrect");
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if (bestpath == NULL || path->path.total_cost < bestpath->path.total_cost) {
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bestpath = path;
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bestrinfo = rinfo;
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}
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}
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}
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}
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/* Fail if no suitable clauses found */
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if (bestpath == NULL)
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return false;
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/*
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* Convert the path's indexclauses structure to a RestrictInfo tree. We
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* include any partial-index predicates so as to get a reasonable
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* representation of what the path is actually scanning.
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*/
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newrinfos = make_restrictinfo_from_bitmapqual((Path*)bestpath, true, true);
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/* It's possible we get back something other than a single OR clause */
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if (list_length(newrinfos) != 1)
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return false;
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or_rinfo = (RestrictInfo*)linitial(newrinfos);
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AssertEreport(IsA(or_rinfo, RestrictInfo), MOD_OPT, "Restriction clause does not contain OR");
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if (!restriction_is_or_clause(or_rinfo))
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return false;
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/*
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* OK, add it to the rel's restriction list.
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*/
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rel->baserestrictinfo = list_concat(rel->baserestrictinfo, newrinfos);
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rel->baserestrict_min_security = Min(rel->baserestrict_min_security, or_rinfo->security_level);
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/*
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* Adjust the original OR clause's cached selectivity to compensate for
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* the selectivity of the added (but redundant) lower-level qual. This
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* should result in the join rel getting approximately the same rows
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* estimate as it would have gotten without all these shenanigans. (XXX
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* major hack alert ... this depends on the assumption that the
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* selectivity will stay cached ...)
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* we don't need cache the selectivity because the index's selectivity is not accurate.
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*/
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or_selec = clause_selectivity(root, (Node*)or_rinfo, 0, JOIN_INNER, NULL, false);
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if (or_selec > 0 && or_selec < 1) {
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orig_selec = clause_selectivity(root, (Node*)bestrinfo, 0, JOIN_INNER, NULL, false);
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bestrinfo->norm_selec = orig_selec / or_selec;
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/* clamp result to sane range */
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if (bestrinfo->norm_selec > 1)
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bestrinfo->norm_selec = 1;
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/* It isn't an outer join clause, so no need to adjust outer_selec */
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}
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/* Tell caller to recompute partial index status and rowcount estimate */
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return true;
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}
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@ -27,6 +27,7 @@
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#include "parser/parse_hint.h"
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#include "pgxc/pgxc.h"
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#include "optimizer/cost.h"
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#include "optimizer/orclauses.h"
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#include "optimizer/pathnode.h"
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#include "optimizer/paths.h"
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#include "optimizer/placeholder.h"
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@ -239,6 +240,12 @@ void query_planner(PlannerInfo* root, List* tlist, double tuple_fraction, double
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*/
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add_placeholders_to_base_rels(root);
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/*
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* Look for join OR clauses that we can extract single-relation
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* restriction OR clauses from.
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*/
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extract_restriction_or_clauses(root);
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/*
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* We should now have size estimates for every actual table involved in
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* the query, and we also know which if any have been deleted from the
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@ -19,7 +19,7 @@ endif
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SUBDIRS = learn
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OBJS = clauses.o joininfo.o pathnode.o placeholder.o plancat.o predtest.o \
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OBJS = clauses.o joininfo.o orclauses.o pathnode.o placeholder.o plancat.o predtest.o \
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relnode.o restrictinfo.o tlist.o var.o pruningboundary.o pgxcship.o pruning.o randomplan.o optimizerdebug.o planmem_walker.o \
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nodegroups.o plananalyzer.o optcommon.o dataskew.o joinskewinfo.o autoanalyzer.o bucketinfo.o bucketpruning.o
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332
src/gausskernel/optimizer/util/orclauses.cpp
Normal file
332
src/gausskernel/optimizer/util/orclauses.cpp
Normal file
@ -0,0 +1,332 @@
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/*-------------------------------------------------------------------------
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*
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* orclauses.cpp
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* Routines to extract restriction OR clauses from join OR clauses
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*
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* Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
|
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* Portions Copyright (c) 1994, Regents of the University of California
|
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* Portions Copyright (c) 2020 Huawei Technologies Co.,Ltd.
|
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*
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*
|
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* IDENTIFICATION
|
||||
* src/gausskernel/optimizer/util/orclauses.cpp
|
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*
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* -------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "optimizer/clauses.h"
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#include "optimizer/cost.h"
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#include "optimizer/orclauses.h"
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#include "optimizer/restrictinfo.h"
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static bool is_safe_restriction_clause_for(RestrictInfo* rinfo, RelOptInfo* rel);
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static Expr* extract_or_clause(RestrictInfo* or_rinfo, RelOptInfo* rel);
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static void consider_new_or_clause(PlannerInfo* root, RelOptInfo* rel, Expr* orclause, RestrictInfo* join_or_rinfo);
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/*
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* extract_restriction_or_clauses
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* Examine join OR-of-AND clauses to see if any useful restriction OR
|
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* clauses can be extracted. If so, add them to the query.
|
||||
*
|
||||
* Although a join clause must reference multiple relations overall,
|
||||
* an OR of ANDs clause might contain sub-clauses that reference just one
|
||||
* relation and can be used to build a restriction clause for that rel.
|
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* For example consider
|
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* WHERE ((a.x = 42 AND b.y = 43) OR (a.x = 44 AND b.z = 45));
|
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* We can transform this into
|
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* WHERE ((a.x = 42 AND b.y = 43) OR (a.x = 44 AND b.z = 45))
|
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* AND (a.x = 42 OR a.x = 44)
|
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* AND (b.y = 43 OR b.z = 45);
|
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* which allows the latter clauses to be applied during the scans of a and b,
|
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* perhaps as index qualifications, and in any case reducing the number of
|
||||
* rows arriving at the join. In essence this is a partial transformation to
|
||||
* CNF (AND of ORs format). It is not complete, however, because we do not
|
||||
* unravel the original OR --- doing so would usually bloat the qualification
|
||||
* expression to little gain.
|
||||
*
|
||||
* The added quals are partially redundant with the original OR, and therefore
|
||||
* would cause the size of the joinrel to be underestimated when it is finally
|
||||
* formed. (This would be true of a full transformation to CNF as well; the
|
||||
* fault is not really in the transformation, but in clauselist_selectivity's
|
||||
* inability to recognize redundant conditions.) We can compensate for this
|
||||
* redundancy by changing the cached selectivity of the original OR clause,
|
||||
* cancelling out the (valid) reduction in the estimated sizes of the base
|
||||
* relations so that the estimated joinrel size remains the same. This is
|
||||
* a MAJOR HACK: it depends on the fact that clause selectivities are cached
|
||||
* and on the fact that the same RestrictInfo node will appear in every
|
||||
* joininfo list that might be used when the joinrel is formed.
|
||||
* And it doesn't work in cases where the size estimation is nonlinear
|
||||
* (i.e., outer and IN joins). But it beats not doing anything.
|
||||
*
|
||||
* We examine each base relation to see if join clauses associated with it
|
||||
* contain extractable restriction conditions. If so, add those conditions
|
||||
* to the rel's baserestrictinfo and update the cached selectivities of the
|
||||
* join clauses. Note that the same join clause will be examined afresh
|
||||
* from the point of view of each baserel that participates in it, so its
|
||||
* cached selectivity may get updated multiple times.
|
||||
*/
|
||||
void extract_restriction_or_clauses(PlannerInfo* root)
|
||||
{
|
||||
/* Examine each baserel for potential join OR clauses */
|
||||
for (int rti = 1; rti < root->simple_rel_array_size; rti++) {
|
||||
RelOptInfo* rel = root->simple_rel_array[rti];
|
||||
ListCell* lc = NULL;
|
||||
|
||||
/* there may be empty slots corresponding to non-baserel RTEs */
|
||||
if (rel == NULL) {
|
||||
continue;
|
||||
}
|
||||
|
||||
Assert(rel->relid == (uint)rti); /* sanity check on array */
|
||||
|
||||
/* ignore RTEs that are "other rels" */
|
||||
if (rel->reloptkind != RELOPT_BASEREL) {
|
||||
continue;
|
||||
}
|
||||
|
||||
/*
|
||||
* Find potentially interesting OR joinclauses. We can use any
|
||||
* joinclause that is considered safe to move to this rel by the
|
||||
* parameterized-path machinery, even though what we are going to do
|
||||
* with it is not exactly a parameterized path.
|
||||
*
|
||||
* However, it seems best to ignore clauses that have been marked
|
||||
* redundant (by setting norm_selec > 1). That likely can't happen
|
||||
* for OR clauses, but let's be safe.
|
||||
*/
|
||||
foreach (lc, rel->joininfo) {
|
||||
RestrictInfo* rinfo = (RestrictInfo*)lfirst(lc);
|
||||
|
||||
if (restriction_is_or_clause(rinfo) && join_clause_is_movable_to(rinfo, rel->relid) &&
|
||||
rinfo->norm_selec <= 1) {
|
||||
/* Try to extract a qual for this rel only */
|
||||
Expr* orclause = extract_or_clause(rinfo, rel);
|
||||
|
||||
/*
|
||||
* If successful, decide whether we want to use the clause,
|
||||
* and insert it into the rel's restrictinfo list if so.
|
||||
*/
|
||||
if (orclause) {
|
||||
consider_new_or_clause(root, rel, orclause, rinfo);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Is the given primitive (non-OR) RestrictInfo safe to move to the rel?
|
||||
*/
|
||||
static bool is_safe_restriction_clause_for(RestrictInfo* rinfo, RelOptInfo* rel)
|
||||
{
|
||||
/*
|
||||
* We want clauses that mention the rel, and only the rel. So in
|
||||
* particular pseudoconstant clauses can be rejected quickly. Then check
|
||||
* the clause's Var membership.
|
||||
*/
|
||||
if (rinfo->pseudoconstant) {
|
||||
return false;
|
||||
}
|
||||
if (!bms_equal(rinfo->clause_relids, rel->relids)) {
|
||||
return false;
|
||||
}
|
||||
|
||||
/* We don't want extra evaluations of any volatile functions */
|
||||
if (contain_volatile_functions((Node*)rinfo->clause)) {
|
||||
return false;
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
/*
|
||||
* Try to extract a restriction clause mentioning only "rel" from the given
|
||||
* join OR-clause.
|
||||
*
|
||||
* We must be able to extract at least one qual for this rel from each of
|
||||
* the arms of the OR, else we can't use it.
|
||||
*
|
||||
* Returns an OR clause (not a RestrictInfo!) pertaining to rel, or NULL
|
||||
* if no OR clause could be extracted.
|
||||
*/
|
||||
static Expr* extract_or_clause(RestrictInfo* or_rinfo, RelOptInfo* rel)
|
||||
{
|
||||
List* clauselist = NIL;
|
||||
ListCell* lc = NULL;
|
||||
|
||||
/*
|
||||
* Scan each arm of the input OR clause. Notice we descend into
|
||||
* or_rinfo->orclause, which has RestrictInfo nodes embedded below the
|
||||
* toplevel OR/AND structure. This is useful because we can use the info
|
||||
* in those nodes to make is_safe_restriction_clause_for()'s checks
|
||||
* cheaper. We'll strip those nodes from the returned tree, though,
|
||||
* meaning that fresh ones will be built if the clause is accepted as a
|
||||
* restriction clause. This might seem wasteful --- couldn't we re-use
|
||||
* the existing RestrictInfos? But that'd require assuming that
|
||||
* selectivity and other cached data is computed exactly the same way for
|
||||
* a restriction clause as for a join clause, which seems undesirable.
|
||||
*/
|
||||
Assert(or_clause((Node*)or_rinfo->orclause));
|
||||
foreach (lc, ((BoolExpr*)or_rinfo->orclause)->args) {
|
||||
Node* orarg = (Node*)lfirst(lc);
|
||||
List* subclauses = NIL;
|
||||
Node* subclause = NULL;
|
||||
|
||||
/* OR arguments should be ANDs or sub-RestrictInfos */
|
||||
if (and_clause(orarg)) {
|
||||
List* andargs = ((BoolExpr*)orarg)->args;
|
||||
ListCell* lc2 = NULL;
|
||||
|
||||
foreach (lc2, andargs) {
|
||||
RestrictInfo* rinfo = (RestrictInfo*)lfirst(lc2);
|
||||
|
||||
Assert(IsA(rinfo, RestrictInfo));
|
||||
if (restriction_is_or_clause(rinfo)) {
|
||||
/*
|
||||
* Recurse to deal with nested OR. Note we *must* recurse
|
||||
* here, this isn't just overly-tense optimization: we
|
||||
* have to descend far enough to find and strip all
|
||||
* RestrictInfos in the expression.
|
||||
*/
|
||||
Expr* suborclause = NULL;
|
||||
|
||||
suborclause = extract_or_clause(rinfo, rel);
|
||||
if (suborclause) {
|
||||
subclauses = lappend(subclauses, suborclause);
|
||||
}
|
||||
} else if (is_safe_restriction_clause_for(rinfo, rel)) {
|
||||
subclauses = lappend(subclauses, rinfo->clause);
|
||||
}
|
||||
}
|
||||
} else {
|
||||
Assert(IsA(orarg, RestrictInfo));
|
||||
Assert(!restriction_is_or_clause((RestrictInfo*)orarg));
|
||||
if (is_safe_restriction_clause_for((RestrictInfo*)orarg, rel)) {
|
||||
subclauses = lappend(subclauses, ((RestrictInfo*)orarg)->clause);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* If nothing could be extracted from this arm, we can't do anything
|
||||
* with this OR clause.
|
||||
*/
|
||||
if (subclauses == NIL) {
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/*
|
||||
* OK, add subclause(s) to the result OR. If we found more than one,
|
||||
* we need an AND node. But if we found only one, and it is itself an
|
||||
* OR node, add its subclauses to the result instead; this is needed
|
||||
* to preserve AND/OR flatness (ie, no OR directly underneath OR).
|
||||
*/
|
||||
clauselist = lappend(clauselist, make_ands_explicit(subclauses));
|
||||
subclause = (Node*)make_ands_explicit(subclauses);
|
||||
if (or_clause(subclause)) {
|
||||
clauselist = list_concat(clauselist, list_copy(((BoolExpr*)subclause)->args));
|
||||
} else {
|
||||
clauselist = lappend(clauselist, subclause);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* If we got a restriction clause from every arm, wrap them up in an OR
|
||||
* node. (In theory the OR node might be unnecessary, if there was only
|
||||
* one arm --- but then the input OR node was also redundant.)
|
||||
*/
|
||||
if (clauselist != NIL) {
|
||||
return make_orclause(clauselist);
|
||||
}
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/*
|
||||
* Consider whether a successfully-extracted restriction OR clause is
|
||||
* actually worth using. If so, add it to the planner's data structures,
|
||||
* and adjust the original join clause (join_or_rinfo) to compensate.
|
||||
*/
|
||||
static void consider_new_or_clause(PlannerInfo* root, RelOptInfo* rel, Expr* orclause, RestrictInfo* join_or_rinfo)
|
||||
{
|
||||
RestrictInfo* or_rinfo = NULL;
|
||||
Selectivity or_selec, orig_selec;
|
||||
|
||||
/*
|
||||
* Build a RestrictInfo from the new OR clause. We can assume it's valid
|
||||
* as a base restriction clause.
|
||||
*/
|
||||
or_rinfo = make_restrictinfo(orclause, true, false, false, join_or_rinfo->security_level, NULL, NULL, NULL);
|
||||
|
||||
/*
|
||||
* Estimate its selectivity. (We could have done this earlier, but doing
|
||||
* it on the RestrictInfo representation allows the result to get cached,
|
||||
* saving work later.)
|
||||
*/
|
||||
or_selec = clause_selectivity(root, (Node*)or_rinfo, 0, JOIN_INNER, NULL);
|
||||
|
||||
/*
|
||||
* The clause is only worth adding to the query if it rejects a useful
|
||||
* fraction of the base relation's rows; otherwise, it's just going to
|
||||
* cause duplicate computation (since we will still have to check the
|
||||
* original OR clause when the join is formed). Somewhat arbitrarily, we
|
||||
* set the selectivity threshold at 0.9.
|
||||
*/
|
||||
if (or_selec > 0.9) {
|
||||
return; /* forget it */
|
||||
}
|
||||
/*
|
||||
* OK, add it to the rel's restriction-clause list.
|
||||
*/
|
||||
rel->baserestrictinfo = lappend(rel->baserestrictinfo, or_rinfo);
|
||||
|
||||
/*
|
||||
* Adjust the original join OR clause's cached selectivity to compensate
|
||||
* for the selectivity of the added (but redundant) lower-level qual. This
|
||||
* should result in the join rel getting approximately the same rows
|
||||
* estimate as it would have gotten without all these shenanigans.
|
||||
*
|
||||
* XXX major hack alert: this depends on the assumption that the
|
||||
* selectivity will stay cached.
|
||||
*
|
||||
* XXX another major hack: we adjust only norm_selec, the cached
|
||||
* selectivity for JOIN_INNER semantics, even though the join clause
|
||||
* might've been an outer-join clause. This is partly because we can't
|
||||
* easily identify the relevant SpecialJoinInfo here, and partly because
|
||||
* the linearity assumption we're making would fail anyway. (If it is an
|
||||
* outer-join clause, "rel" must be on the nullable side, else we'd not
|
||||
* have gotten here. So the computation of the join size is going to be
|
||||
* quite nonlinear with respect to the size of "rel", so it's not clear
|
||||
* how we ought to adjust outer_selec even if we could compute its
|
||||
* original value correctly.)
|
||||
*/
|
||||
if (or_selec > 0) {
|
||||
SpecialJoinInfo sjinfo;
|
||||
|
||||
/*
|
||||
* Make up a SpecialJoinInfo for JOIN_INNER semantics. (Compare
|
||||
* approx_tuple_count() in costsize.c.)
|
||||
*/
|
||||
sjinfo.type = T_SpecialJoinInfo;
|
||||
sjinfo.min_lefthand = bms_difference(join_or_rinfo->clause_relids, rel->relids);
|
||||
sjinfo.min_righthand = rel->relids;
|
||||
sjinfo.syn_lefthand = sjinfo.min_lefthand;
|
||||
sjinfo.syn_righthand = sjinfo.min_righthand;
|
||||
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;
|
||||
|
||||
/* Compute inner-join size */
|
||||
orig_selec = clause_selectivity(root, (Node*)join_or_rinfo, 0, JOIN_INNER, &sjinfo);
|
||||
|
||||
/* And hack cached selectivity so join size remains the same */
|
||||
join_or_rinfo->norm_selec = orig_selec / or_selec;
|
||||
/* ensure result stays in sane range, in particular not "redundant" */
|
||||
if (join_or_rinfo->norm_selec > 1) {
|
||||
join_or_rinfo->norm_selec = 1;
|
||||
}
|
||||
/* as explained above, we don't touch outer_selec */
|
||||
}
|
||||
}
|
||||
21
src/include/optimizer/orclauses.h
Normal file
21
src/include/optimizer/orclauses.h
Normal file
@ -0,0 +1,21 @@
|
||||
/*-------------------------------------------------------------------------
|
||||
*
|
||||
* orclauses.h
|
||||
* prototypes for orclauses.cpp.
|
||||
*
|
||||
*
|
||||
* Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* src/include/optimizer/orclauses.h
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
#ifndef ORCLAUSES_H
|
||||
#define ORCLAUSES_H
|
||||
|
||||
#include "nodes/relation.h"
|
||||
|
||||
extern void extract_restriction_or_clauses(PlannerInfo *root);
|
||||
|
||||
#endif /* ORCLAUSES_H */
|
||||
@ -22,11 +22,10 @@ explain (costs off, verbose on) execute s (1,1);
|
||||
explain (costs off, verbose on) execute i (6,6,6);
|
||||
QUERY PLAN
|
||||
----------------------------
|
||||
[Bypass]
|
||||
Insert on public.t1_xc_fqs
|
||||
-> Result
|
||||
Output: 6, 6, 6
|
||||
(4 rows)
|
||||
(3 rows)
|
||||
|
||||
explain (costs off, verbose on) execute u (2,2);
|
||||
QUERY PLAN
|
||||
@ -189,11 +188,10 @@ explain (costs off, verbose on) execute s (1);
|
||||
explain (costs off, verbose on) execute i (6);
|
||||
QUERY PLAN
|
||||
----------------------------
|
||||
[Bypass]
|
||||
Insert on public.t1_xc_fqs
|
||||
-> Result
|
||||
Output: 6, 2, 3
|
||||
(4 rows)
|
||||
(3 rows)
|
||||
|
||||
explain (costs off, verbose on) execute u (2);
|
||||
QUERY PLAN
|
||||
@ -2558,11 +2556,10 @@ explain (costs off, verbose on) execute s (1);
|
||||
explain (costs off, verbose on) execute i (6);
|
||||
QUERY PLAN
|
||||
----------------------------
|
||||
[Bypass]
|
||||
Insert on public.t1_xc_fqs
|
||||
-> Result
|
||||
Output: 6, 2, 3
|
||||
(4 rows)
|
||||
(3 rows)
|
||||
|
||||
explain (costs off, verbose on) execute u (2);
|
||||
QUERY PLAN
|
||||
@ -3644,15 +3641,16 @@ INSERT INTO pbe_prunning_002 values (1, 1, 1);
|
||||
SET enable_pbe_optimization to false;
|
||||
PREPARE pa AS SELECT * FROM pbe_prunning_001 pp1 RIGHT OUTER JOIN pbe_prunning_002 pp2 ON pp1.c_int=pp2.c_int WHERE (pp1.c_int=$1 AND pp1.c_numeric=$2 AND pp2.c_int=$3 AND pp2.c_numeric=$4) or pp1.id=$5;
|
||||
EXPLAIN(COSTS FALSE) EXECUTE pa(10,10,10,10,11);
|
||||
QUERY PLAN
|
||||
-----------------------------------------------------------------------------------------------------------------------------------------------
|
||||
QUERY PLAN
|
||||
------------------------------------------------------------------------------------------------------------------------------------------------
|
||||
Hash Join
|
||||
Hash Cond: (pp1.c_int = pp2.c_int)
|
||||
Hash Cond: (pp2.c_int = pp1.c_int)
|
||||
Join Filter: (((pp1.c_int = 10) AND (pp1.c_numeric = 10::numeric) AND (pp2.c_int = 10) AND (pp2.c_numeric = 10::numeric)) OR (pp1.id = 11))
|
||||
-> Seq Scan on pbe_prunning_001 pp1
|
||||
-> Seq Scan on pbe_prunning_002 pp2
|
||||
-> Hash
|
||||
-> Seq Scan on pbe_prunning_002 pp2
|
||||
(6 rows)
|
||||
-> Seq Scan on pbe_prunning_001 pp1
|
||||
Filter: (((c_int = 10) AND (c_numeric = 10::numeric)) OR ((c_int = 10) AND (c_numeric = 10::numeric)) OR (id = 11) OR (id = 11))
|
||||
(7 rows)
|
||||
|
||||
DEALLOCATE PREPARE pa;
|
||||
DROP TABLE pbe_prunning_001;
|
||||
|
||||
@ -21,11 +21,10 @@ explain (costs off, verbose on) execute s (1,1);
|
||||
explain (costs off, verbose on) execute i (6,6,6);
|
||||
QUERY PLAN
|
||||
----------------------------
|
||||
[Bypass]
|
||||
Insert on public.t1_xc_fqs
|
||||
-> Result
|
||||
Output: 6, 6, 6
|
||||
(4 rows)
|
||||
(3 rows)
|
||||
|
||||
explain (costs off, verbose on) execute u (2,2);
|
||||
QUERY PLAN
|
||||
@ -188,11 +187,10 @@ explain (costs off, verbose on) execute s (1);
|
||||
explain (costs off, verbose on) execute i (6);
|
||||
QUERY PLAN
|
||||
----------------------------
|
||||
[Bypass]
|
||||
Insert on public.t1_xc_fqs
|
||||
-> Result
|
||||
Output: 6, 2, 3
|
||||
(4 rows)
|
||||
(3 rows)
|
||||
|
||||
explain (costs off, verbose on) execute u (2);
|
||||
QUERY PLAN
|
||||
@ -2557,11 +2555,10 @@ explain (costs off, verbose on) execute s (1);
|
||||
explain (costs off, verbose on) execute i (6);
|
||||
QUERY PLAN
|
||||
----------------------------
|
||||
[Bypass]
|
||||
Insert on public.t1_xc_fqs
|
||||
-> Result
|
||||
Output: 6, 2, 3
|
||||
(4 rows)
|
||||
(3 rows)
|
||||
|
||||
explain (costs off, verbose on) execute u (2);
|
||||
QUERY PLAN
|
||||
@ -3642,15 +3639,16 @@ INSERT INTO pbe_prunning_001 values (1, 1, 1);
|
||||
INSERT INTO pbe_prunning_002 values (1, 1, 1);
|
||||
PREPARE pa AS SELECT * FROM pbe_prunning_001 pp1 RIGHT OUTER JOIN pbe_prunning_002 pp2 ON pp1.c_int=pp2.c_int WHERE (pp1.c_int=$1 AND pp1.c_numeric=$2 AND pp2.c_int=$3 AND pp2.c_numeric=$4) or pp1.id=$5;
|
||||
EXPLAIN(COSTS FALSE) EXECUTE pa(10,10,10,10,11);
|
||||
QUERY PLAN
|
||||
-----------------------------------------------------------------------------------------------------------------------------
|
||||
QUERY PLAN
|
||||
------------------------------------------------------------------------------------------------------------------------------
|
||||
Hash Join
|
||||
Hash Cond: (pp1.c_int = pp2.c_int)
|
||||
Hash Cond: (pp2.c_int = pp1.c_int)
|
||||
Join Filter: (((pp1.c_int = $1) AND (pp1.c_numeric = $2) AND (pp2.c_int = $3) AND (pp2.c_numeric = $4)) OR (pp1.id = $5))
|
||||
-> Seq Scan on pbe_prunning_001 pp1
|
||||
-> Seq Scan on pbe_prunning_002 pp2
|
||||
-> Hash
|
||||
-> Seq Scan on pbe_prunning_002 pp2
|
||||
(6 rows)
|
||||
-> Seq Scan on pbe_prunning_001 pp1
|
||||
Filter: (((c_int = $1) AND (c_numeric = $2)) OR ((c_int = $1) AND (c_numeric = $2)) OR (id = $5) OR (id = $5))
|
||||
(7 rows)
|
||||
|
||||
DEALLOCATE PREPARE pa;
|
||||
DROP TABLE pbe_prunning_001;
|
||||
|
||||
@ -67,13 +67,15 @@ order by
|
||||
Join Filter: (((n1.n_name = 'FRANCE '::bpchar) AND (n2.n_name = 'GERMANY'::bpchar)) OR ((n1.n_name = 'GERMANY'::bpchar) AND (n2.n_name = 'FRANCE'::bpchar)))
|
||||
-> Row Adapter
|
||||
-> CStore Scan on nation n1
|
||||
Filter: ((n_name = 'FRANCE '::bpchar) OR (n_name = 'FRANCE '::bpchar) OR (n_name = 'GERMANY'::bpchar) OR (n_name = 'GERMANY'::bpchar))
|
||||
-> Materialize
|
||||
-> Row Adapter
|
||||
-> CStore Scan on nation n2
|
||||
Filter: ((n_name = 'GERMANY'::bpchar) OR (n_name = 'GERMANY'::bpchar) OR (n_name = 'FRANCE'::bpchar) OR (n_name = 'FRANCE'::bpchar))
|
||||
-> Hash
|
||||
-> Row Adapter
|
||||
-> CStore Scan on supplier
|
||||
(32 rows)
|
||||
(34 rows)
|
||||
|
||||
select
|
||||
supp_nation,
|
||||
|
||||
@ -61,10 +61,12 @@ order by
|
||||
-> Vector Nest Loop
|
||||
Join Filter: (((n1.n_name = 'FRANCE '::bpchar) AND (n2.n_name = 'GERMANY'::bpchar)) OR ((n1.n_name = 'GERMANY'::bpchar) AND (n2.n_name = 'FRANCE'::bpchar)))
|
||||
-> CStore Scan on nation n1
|
||||
Filter: ((n_name = 'FRANCE '::bpchar) OR (n_name = 'FRANCE '::bpchar) OR (n_name = 'GERMANY'::bpchar) OR (n_name = 'GERMANY'::bpchar))
|
||||
-> Vector Materialize
|
||||
-> CStore Scan on nation n2
|
||||
Filter: ((n_name = 'GERMANY'::bpchar) OR (n_name = 'GERMANY'::bpchar) OR (n_name = 'FRANCE'::bpchar) OR (n_name = 'FRANCE'::bpchar))
|
||||
-> CStore Scan on supplier
|
||||
(23 rows)
|
||||
(25 rows)
|
||||
|
||||
select
|
||||
supp_nation,
|
||||
|
||||
@ -387,7 +387,8 @@ test: xc_groupby xc_distkey xc_having
|
||||
#test: hw_rewrite_lazyagg hw_light
|
||||
test: xc_temp xc_FQS
|
||||
#test: xc_remote hw_pbe
|
||||
test: xc_FQS_join xc_copy
|
||||
test: hw_pbe
|
||||
test: xc_FQS_join xc_copy
|
||||
#test: xc_alter_table
|
||||
test: xc_constraints xc_limit xc_sort
|
||||
#test: xc_params xc_returning_step1
|
||||
@ -558,7 +559,7 @@ test: hw_pwd_reuse
|
||||
|
||||
test: performance_enhance
|
||||
test: explain_fqs
|
||||
#test: explain_pbe
|
||||
test: explain_pbe
|
||||
# temp__3 create_table copy vec_prepare_001 vec_prepare_002 vec_prepare_003 int4 int8 are duplicated
|
||||
test: temp__3
|
||||
# ----------
|
||||
|
||||
Reference in New Issue
Block a user