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@ -7,7 +7,7 @@ |
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* |
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* |
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* IDENTIFICATION |
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* $Header: /cvsroot/pgsql/src/backend/optimizer/path/joinpath.c,v 1.7 1998/07/18 04:22:32 momjian Exp $ |
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* $Header: /cvsroot/pgsql/src/backend/optimizer/path/joinpath.c,v 1.8 1998/08/04 16:44:07 momjian Exp $ |
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* |
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*------------------------------------------------------------------------- |
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*/ |
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@ -27,7 +27,7 @@ |
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#include "optimizer/pathnode.h" |
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#include "optimizer/keys.h" |
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#include "optimizer/cost.h" /* for _enable_{hashjoin, |
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* _enable_mergesort} */ |
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* _enable_mergejoin} */ |
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static Path *best_innerjoin(List *join_paths, List *outer_relid); |
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static List * |
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@ -98,7 +98,7 @@ find_all_join_paths(Query *root, List *joinrels) |
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bestinnerjoin = best_innerjoin(innerrel->innerjoin, |
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outerrel->relids); |
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if (_enable_mergesort_) |
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if (_enable_mergejoin_) |
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{ |
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mergeinfo_list = |
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group_clauses_by_order(joinrel->clauseinfo, |
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@ -116,7 +116,7 @@ find_all_join_paths(Query *root, List *joinrels) |
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joinrel->relids = intAppend(outerrelids, innerrelids); |
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/*
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* 1. Consider mergesort paths where both relations must be |
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* 1. Consider mergejoin paths where both relations must be |
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* explicitly sorted. |
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*/ |
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pathlist = sort_inner_and_outer(joinrel, outerrel, |
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@ -125,7 +125,7 @@ find_all_join_paths(Query *root, List *joinrels) |
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/*
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* 2. Consider paths where the outer relation need not be |
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* explicitly sorted. This may include either nestloops and |
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* mergesorts where the outer path is already ordered. |
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* mergejoins where the outer path is already ordered. |
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*/ |
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pathlist = |
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add_pathlist(joinrel, pathlist, |
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@ -139,7 +139,7 @@ find_all_join_paths(Query *root, List *joinrels) |
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/*
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* 3. Consider paths where the inner relation need not be |
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* explicitly sorted. This may include nestloops and mergesorts |
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* explicitly sorted. This may include nestloops and mergejoins |
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* the actual nestloop nodes were constructed in |
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* (match-unsorted-outer). |
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*/ |
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@ -226,16 +226,16 @@ best_innerjoin(List *join_paths, List *outer_relids) |
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/*
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* sort-inner-and-outer-- |
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* Create mergesort join paths by explicitly sorting both the outer and |
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* Create mergejoin join paths by explicitly sorting both the outer and |
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* inner join relations on each available merge ordering. |
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* |
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* 'joinrel' is the join relation |
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* 'outerrel' is the outer join relation |
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* 'innerrel' is the inner join relation |
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* 'mergeinfo-list' is a list of nodes containing info on(mergesortable) |
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* 'mergeinfo-list' is a list of nodes containing info on(mergejoinable) |
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* clauses for joining the relations |
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* |
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* Returns a list of mergesort paths. |
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* Returns a list of mergejoin paths. |
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*/ |
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static List * |
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sort_inner_and_outer(RelOptInfo *joinrel, |
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@ -270,7 +270,7 @@ sort_inner_and_outer(RelOptInfo *joinrel, |
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xmergeinfo->jmethod.clauses); |
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temp_node = |
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create_mergesort_path(joinrel, |
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create_mergejoin_path(joinrel, |
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outerrel->size, |
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innerrel->size, |
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outerrel->width, |
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@ -292,12 +292,12 @@ sort_inner_and_outer(RelOptInfo *joinrel, |
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* match-unsorted-outer-- |
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* Creates possible join paths for processing a single join relation |
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* 'joinrel' by employing either iterative substitution or |
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* mergesorting on each of its possible outer paths(assuming that the |
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* mergejoining on each of its possible outer paths(assuming that the |
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* outer relation need not be explicitly sorted). |
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* |
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* 1. The inner path is the cheapest available inner path. |
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* 2. Mergesort wherever possible. Mergesorts are considered if there |
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* are mergesortable join clauses between the outer and inner join |
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* 2. Mergejoin wherever possible. Mergejoin are considered if there |
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* are mergejoinable join clauses between the outer and inner join |
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* relations such that the outer path is keyed on the variables |
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* appearing in the clauses. The corresponding inner merge path is |
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* either a path whose keys match those of the outer path(if such a |
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@ -310,7 +310,7 @@ sort_inner_and_outer(RelOptInfo *joinrel, |
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* 'outerpath-list' is the list of possible outer paths |
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* 'cheapest-inner' is the cheapest inner path |
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* 'best-innerjoin' is the best inner index path(if any) |
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* 'mergeinfo-list' is a list of nodes containing info on mergesortable |
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* 'mergeinfo-list' is a list of nodes containing info on mergejoinable |
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* clauses |
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* |
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* Returns a list of possible join path nodes. |
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@ -424,7 +424,7 @@ match_unsorted_outer(RelOptInfo *joinrel, |
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mergeinnerpath = cheapest_inner; |
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temp_node = |
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lcons(create_mergesort_path(joinrel, |
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lcons(create_mergejoin_path(joinrel, |
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outerrel->size, |
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innerrel->size, |
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outerrel->width, |
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@ -463,7 +463,7 @@ match_unsorted_outer(RelOptInfo *joinrel, |
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* 'outerrel' is the outer join relation |
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* 'innerrel' is the inner join relation |
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* 'innerpath-list' is the list of possible inner join paths |
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* 'mergeinfo-list' is a list of nodes containing info on mergesortable |
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* 'mergeinfo-list' is a list of nodes containing info on mergejoinable |
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* clauses |
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* |
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* Returns a list of possible merge paths. |
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@ -542,7 +542,7 @@ match_unsorted_inner(RelOptInfo *joinrel, |
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clauses); |
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temp_node = |
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lcons(create_mergesort_path(joinrel, |
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lcons(create_mergejoin_path(joinrel, |
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outerrel->size, |
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innerrel->size, |
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outerrel->width, |
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Bruce Momjian
28 years ago