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optimizer cleanup

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This commit is contained in:
Bruce Momjian
1999-02-19 02:05:20 +00:00
parent 61f40ac3f2
commit 8ab72a38df
5 changed files with 76 additions and 77 deletions
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115
src/backend/optimizer/path/pathkey.c
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@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/Attic/pathkey.c,v 1.1 1999/02/18 19:58:52 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/Attic/pathkey.c,v 1.2 1999/02/19 02:05:15 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -27,9 +27,9 @@
static int match_pathkey_joinkeys(List *pathkey, List *joinkeys,
int which_subkey);
int outer_or_inner);
static bool every_func(List *joinkeys, List *pathkey,
int which_subkey);
int outer_or_inner);
static List *new_join_pathkey(List *subkeys, List *considered_subkeys,
List *join_rel_tlist, List *joinclauses);
static List *new_matching_subkeys(Var *subkey, List *considered_subkeys,
@@ -54,7 +54,7 @@ static List *new_matching_subkeys(Var *subkey, List *considered_subkeys,
* ( (outer inner) (outer inner) ... )
* 'joinclauses' is a list of clauses corresponding to the join keys in
* 'joinkeys'
* 'which_subkey' is a flag that selects the desired subkey of a join key
* 'outer_or_inner' is a flag that selects the desired subkey of a join key
* in 'joinkeys'
*
* Returns the join keys and corresponding join clauses in a list if all
@@ -72,7 +72,7 @@ List *
match_pathkeys_joinkeys(List *pathkeys,
List *joinkeys,
List *joinclauses,
int which_subkey,
int outer_or_inner,
List **matchedJoinClausesPtr)
{
List *matched_joinkeys = NIL;
@@ -84,19 +84,17 @@ match_pathkeys_joinkeys(List *pathkeys,
foreach(i, pathkeys)
{
pathkey = lfirst(i);
matched_joinkey_index = match_pathkey_joinkeys(pathkey, joinkeys, which_subkey);
matched_joinkey_index = match_pathkey_joinkeys(pathkey, joinkeys,
outer_or_inner);
if (matched_joinkey_index != -1)
{
List *xjoinkey = nth(matched_joinkey_index, joinkeys);
List *joinclause = nth(matched_joinkey_index, joinclauses);
/* XXX was "push" function */
matched_joinkeys = lappend(matched_joinkeys, xjoinkey);
matched_joinkeys = nreverse(matched_joinkeys);
matched_joinkeys = lcons(xjoinkey, matched_joinkeys);
matched_joinclauses = lcons(joinclause, matched_joinclauses);
matched_joinclauses = lappend(matched_joinclauses, joinclause);
matched_joinclauses = nreverse(matched_joinclauses);
joinkeys = LispRemove(xjoinkey, joinkeys);
}
else
@@ -111,6 +109,7 @@ match_pathkeys_joinkeys(List *pathkeys,
return nreverse(matched_joinkeys);
}
/*
* match_pathkey_joinkeys
* Returns the 0-based index into 'joinkeys' of the first joinkey whose
@@ -119,7 +118,7 @@ match_pathkeys_joinkeys(List *pathkeys,
static int
match_pathkey_joinkeys(List *pathkey,
List *joinkeys,
int which_subkey)
int outer_or_inner)
{
Var *path_subkey;
int pos;
@@ -135,7 +134,7 @@ match_pathkey_joinkeys(List *pathkey,
{
jk = (JoinKey *) lfirst(x);
if (var_equal(path_subkey,
extract_join_subkey(jk, which_subkey)))
extract_join_key(jk, outer_or_inner)))
return pos;
pos++;
}
@@ -143,6 +142,7 @@ match_pathkey_joinkeys(List *pathkey,
return -1; /* no index found */
}
/*
* match_paths_joinkeys
* Attempts to find a path in 'paths' whose keys match a set of join
@@ -159,53 +159,16 @@ match_pathkey_joinkeys(List *pathkey,
* must correspond
* 'paths' is a list of(inner) paths which are to be matched against
* each join key in 'joinkeys'
* 'which_subkey' is a flag that selects the desired subkey of a join key
* 'outer_or_inner' is a flag that selects the desired subkey of a join key
* in 'joinkeys'
*
* Returns the matching path node if one exists, nil otherwise.
*/
static bool
every_func(List *joinkeys, List *pathkey, int which_subkey)
{
JoinKey *xjoinkey;
Var *temp;
Var *tempkey = NULL;
bool found = false;
List *i = NIL;
List *j = NIL;
foreach(i, joinkeys)
{
xjoinkey = (JoinKey *) lfirst(i);
found = false;
foreach(j, pathkey)
{
temp = (Var *) lfirst((List *) lfirst(j));
if (temp == NULL)
continue;
tempkey = extract_join_subkey(xjoinkey, which_subkey);
if (var_equal(tempkey, temp))
{
found = true;
break;
}
}
if (found == false)
return false;
}
return found;
}
/*
* match_paths_joinkeys -
* find the cheapest path that matches the join keys
* Find the cheapest path that matches the join keys
*/
Path *
match_paths_joinkeys(List *joinkeys,
PathOrder *ordering,
List *paths,
int which_subkey)
int outer_or_inner)
{
Path *matched_path = NULL;
bool key_match = false;
@@ -216,13 +179,12 @@ match_paths_joinkeys(List *joinkeys,
Path *path = (Path *) lfirst(i);
int better_sort;
key_match = every_func(joinkeys, path->pathkeys, which_subkey);
key_match = every_func(joinkeys, path->pathkeys, outer_or_inner);
if (pathorder_match(ordering, path->pathorder, &better_sort) &&
better_sort == 0 &&
length(joinkeys) == length(path->pathkeys) && key_match)
{
if (matched_path)
{
if (path->path_cost < matched_path->path_cost)
@@ -236,7 +198,6 @@ match_paths_joinkeys(List *joinkeys,
}
/*
* extract_path_keys
* Builds a subkey list for a path by pulling one of the subkeys from
@@ -245,7 +206,7 @@ match_paths_joinkeys(List *joinkeys,
*
* 'joinkeys' is a list of join key pairs
* 'tlist' is a relation target list
* 'which_subkey' is a flag that selects the desired subkey of a join key
* 'outer_or_inner' is a flag that selects the desired subkey of a join key
* in 'joinkeys'
*
* Returns a list of pathkeys: ((tlvar1)(tlvar2)...(tlvarN)).
@@ -254,7 +215,7 @@ match_paths_joinkeys(List *joinkeys,
List *
extract_path_keys(List *joinkeys,
List *tlist,
int which_subkey)
int outer_or_inner)
{
List *pathkeys = NIL;
List *jk;
@@ -269,7 +230,7 @@ extract_path_keys(List *joinkeys,
/*
* find the right Var in the target list for this key
*/
var = (Var *) extract_join_subkey(jkey, which_subkey);
var = (Var *) extract_join_key(jkey, outer_or_inner);
key = (Var *) matching_tlist_var(var, tlist);
/*
@@ -291,6 +252,42 @@ extract_path_keys(List *joinkeys,
}
/*
* every_func
*/
static bool
every_func(List *joinkeys, List *pathkey, int outer_or_inner)
{
JoinKey *xjoinkey;
Var *temp;
Var *tempkey = NULL;
bool found = false;
List *i = NIL;
List *j = NIL;
foreach(i, joinkeys)
{
xjoinkey = (JoinKey *) lfirst(i);
found = false;
foreach(j, pathkey)
{
temp = (Var *) lfirst((List *) lfirst(j));
if (temp == NULL)
continue;
tempkey = extract_join_key(xjoinkey, outer_or_inner);
if (var_equal(tempkey, temp))
{
found = true;
break;
}
}
if (found == false)
return false;
}
return found;
}
/****************************************************************************
* NEW PATHKEY FORMATION
****************************************************************************/