open-dsi
/
postgres
mirror of https://github.com/postgres/postgres
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Revert "Refactor ChangeVarNodesExtended() using the custom callback"

Browse Source 
This reverts commit 250a718aad.
It shouldn't be pushed during the release freeze.

Reported-by: Tom Lane
Discussion: https://postgr.es/m/E1uBIbY-000owH-0O%40gemulon.postgresql.org
pull/217/head
Alexander Korotkov 8 months ago
parent 250a718aad
commit 2782f3b845
4 changed files with 124 additions and 192 deletions
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Show Stats Download Patch File Download Diff File
  1. 160
      src/backend/optimizer/plan/analyzejoins.c
  2. 138
      src/backend/rewrite/rewriteManip.c
  3. 17
      src/include/rewrite/rewriteManip.h
  4. 1
      src/tools/pgindent/typedefs.list

160
src/backend/optimizer/plan/analyzejoins.c
Unescape View File

@ -74,8 +74,6 @@ static bool is_innerrel_unique_for(PlannerInfo *root,
List *restrictlist,
List **extra_clauses);
static int self_join_candidates_cmp(const void *a, const void *b);
static bool replace_relid_callback(Node *node,
ChangeVarNodes_context *context);
/*
@ -399,8 +397,7 @@ remove_rel_from_query(PlannerInfo *root, RelOptInfo *rel,
{
Assert(subst > 0);
ChangeVarNodesExtended((Node *) sjinf->semi_rhs_exprs, relid, subst,
0, replace_relid_callback);
ChangeVarNodes((Node *) sjinf->semi_rhs_exprs, relid, subst, 0);
}
}
@ -472,8 +469,7 @@ remove_rel_from_query(PlannerInfo *root, RelOptInfo *rel,
sjinfo->ojrelid, subst);
Assert(!bms_is_empty(phv->phrels));
ChangeVarNodesExtended((Node *) phv->phexpr, relid, subst, 0,
replace_relid_callback);
ChangeVarNodes((Node *) phv->phexpr, relid, subst, 0);
Assert(phv->phnullingrels == NULL); /* no need to adjust */
}
@ -527,8 +523,7 @@ remove_rel_from_query(PlannerInfo *root, RelOptInfo *rel,
}
if (subst > 0)
ChangeVarNodesExtended((Node *) otherrel->lateral_vars, relid,
subst, 0, replace_relid_callback);
ChangeVarNodes((Node *) otherrel->lateral_vars, relid, subst, 0);
}
}
@ -762,8 +757,7 @@ remove_rel_from_eclass(EquivalenceClass *ec, SpecialJoinInfo *sjinfo,
RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
if (sjinfo == NULL)
ChangeVarNodesExtended((Node *) rinfo, relid, subst, 0,
replace_relid_callback);
ChangeVarNodes((Node *) rinfo, relid, subst, 0);
else
remove_rel_from_restrictinfo(rinfo, relid, sjinfo->ojrelid);
}
@ -1554,8 +1548,7 @@ update_eclasses(EquivalenceClass *ec, int from, int to)
em->em_jdomain->jd_relids = adjust_relid_set(em->em_jdomain->jd_relids, from, to);
/* We only process inner joins */
ChangeVarNodesExtended((Node *) em->em_expr, from, to, 0,
replace_relid_callback);
ChangeVarNodes((Node *) em->em_expr, from, to, 0);
foreach_node(EquivalenceMember, other, new_members)
{
@ -1589,8 +1582,7 @@ update_eclasses(EquivalenceClass *ec, int from, int to)
continue;
}
ChangeVarNodesExtended((Node *) rinfo, from, to, 0,
replace_relid_callback);
ChangeVarNodes((Node *) rinfo, from, to, 0);
/*
* After switching the clause to the remaining relation, check it for
@ -1685,118 +1677,6 @@ add_non_redundant_clauses(PlannerInfo *root,
}
}
/*
* A custom callback for ChangeVarNodesExtended() providing
* Self-join elimination (SJE) related functionality
*
* SJE needs to skip the RangeTblRef node
* type. During SJE's last step, remove_rel_from_joinlist() removes
* remaining RangeTblRefs with target relid. If ChangeVarNodes() replaces
* the target relid before, remove_rel_from_joinlist() fails to identify
* the nodes to delete.
*
* SJE also needs to change the relids within RestrictInfo's.
*/
static bool
replace_relid_callback(Node *node, ChangeVarNodes_context *context)
{
if (IsA(node, RangeTblRef))
{
return true;
}
else if (IsA(node, RestrictInfo))
{
RestrictInfo *rinfo = (RestrictInfo *) node;
int relid = -1;
bool is_req_equal =
(rinfo->required_relids == rinfo->clause_relids);
bool clause_relids_is_multiple =
(bms_membership(rinfo->clause_relids) == BMS_MULTIPLE);
/*
* Recurse down into clauses if the target relation is present in
* clause_relids or required_relids. We must check required_relids
* because the relation not present in clause_relids might still be
* present somewhere in orclause.
*/
if (bms_is_member(context->rt_index, rinfo->clause_relids) ||
bms_is_member(context->rt_index, rinfo->required_relids))
{
Relids new_clause_relids;
ChangeVarNodesWalkExpression((Node *) rinfo->clause, context);
ChangeVarNodesWalkExpression((Node *) rinfo->orclause, context);
new_clause_relids = adjust_relid_set(rinfo->clause_relids,
context->rt_index,
context->new_index);
/*
* Incrementally adjust num_base_rels based on the change of
* clause_relids, which could contain both base relids and
* outer-join relids. This operation is legal until we remove
* only baserels.
*/
rinfo->num_base_rels -= bms_num_members(rinfo->clause_relids) -
bms_num_members(new_clause_relids);
rinfo->clause_relids = new_clause_relids;
rinfo->left_relids =
adjust_relid_set(rinfo->left_relids, context->rt_index, context->new_index);
rinfo->right_relids =
adjust_relid_set(rinfo->right_relids, context->rt_index, context->new_index);
}
if (is_req_equal)
rinfo->required_relids = rinfo->clause_relids;
else
rinfo->required_relids =
adjust_relid_set(rinfo->required_relids, context->rt_index, context->new_index);
rinfo->outer_relids =
adjust_relid_set(rinfo->outer_relids, context->rt_index, context->new_index);
rinfo->incompatible_relids =
adjust_relid_set(rinfo->incompatible_relids, context->rt_index, context->new_index);
if (rinfo->mergeopfamilies &&
bms_get_singleton_member(rinfo->clause_relids, &relid) &&
clause_relids_is_multiple &&
relid == context->new_index && IsA(rinfo->clause, OpExpr))
{
Expr *leftOp;
Expr *rightOp;
leftOp = (Expr *) get_leftop(rinfo->clause);
rightOp = (Expr *) get_rightop(rinfo->clause);
/*
* For self-join elimination, changing varnos could transform
* "t1.a = t2.a" into "t1.a = t1.a". That is always true as long
* as "t1.a" is not null. We use qual() to check for such a case,
* and then we replace the qual for a check for not null
* (NullTest).
*/
if (leftOp != NULL && equal(leftOp, rightOp))
{
NullTest *ntest = makeNode(NullTest);
ntest->arg = leftOp;
ntest->nulltesttype = IS_NOT_NULL;
ntest->argisrow = false;
ntest->location = -1;
rinfo->clause = (Expr *) ntest;
rinfo->mergeopfamilies = NIL;
rinfo->left_em = NULL;
rinfo->right_em = NULL;
}
Assert(rinfo->orclause == NULL);
}
return true;
}
return false;
}
/*
* Remove a relation after we have proven that it participates only in an
* unneeded unique self-join.
@ -1845,8 +1725,7 @@ remove_self_join_rel(PlannerInfo *root, PlanRowMark *kmark, PlanRowMark *rmark,
foreach_node(RestrictInfo, rinfo, joininfos)
{
remove_join_clause_from_rels(root, rinfo, rinfo->required_relids);
ChangeVarNodesExtended((Node *) rinfo, toRemove->relid, toKeep->relid,
0, replace_relid_callback);
ChangeVarNodes((Node *) rinfo, toRemove->relid, toKeep->relid, 0);
if (bms_membership(rinfo->required_relids) == BMS_MULTIPLE)
jinfo_candidates = lappend(jinfo_candidates, rinfo);
@ -1864,8 +1743,7 @@ remove_self_join_rel(PlannerInfo *root, PlanRowMark *kmark, PlanRowMark *rmark,
restrictlist);
foreach_node(RestrictInfo, rinfo, toRemove->baserestrictinfo)
{
ChangeVarNodesExtended((Node *) rinfo, toRemove->relid, toKeep->relid,
0, replace_relid_callback);
ChangeVarNodes((Node *) rinfo, toRemove->relid, toKeep->relid, 0);
if (bms_membership(rinfo->required_relids) == BMS_MULTIPLE)
jinfo_candidates = lappend(jinfo_candidates, rinfo);
@ -1907,8 +1785,7 @@ remove_self_join_rel(PlannerInfo *root, PlanRowMark *kmark, PlanRowMark *rmark,
{
Node *node = lfirst(lc);
ChangeVarNodesExtended(node, toRemove->relid, toKeep->relid, 0,
replace_relid_callback);
ChangeVarNodes(node, toRemove->relid, toKeep->relid, 0);
if (!list_member(toKeep->reltarget->exprs, node))
toKeep->reltarget->exprs = lappend(toKeep->reltarget->exprs, node);
}
@ -1952,18 +1829,14 @@ remove_self_join_rel(PlannerInfo *root, PlanRowMark *kmark, PlanRowMark *rmark,
* Replace varno in all the query structures, except nodes RangeTblRef
* otherwise later remove_rel_from_joinlist will yield errors.
*/
ChangeVarNodesExtended((Node *) root->parse, toRemove->relid, toKeep->relid,
0, replace_relid_callback);
ChangeVarNodesExtended((Node *) root->parse, toRemove->relid, toKeep->relid, 0, false);
/* Replace links in the planner info */
remove_rel_from_query(root, toRemove, toKeep->relid, NULL, NULL);
/* At last, replace varno in root targetlist and HAVING clause */
ChangeVarNodesExtended((Node *) root->processed_tlist, toRemove->relid,
toKeep->relid, 0, replace_relid_callback);
ChangeVarNodesExtended((Node *) root->processed_groupClause,
toRemove->relid, toKeep->relid, 0,
replace_relid_callback);
ChangeVarNodes((Node *) root->processed_tlist, toRemove->relid, toKeep->relid, 0);
ChangeVarNodes((Node *) root->processed_groupClause, toRemove->relid, toKeep->relid, 0);
adjust_relid_set(root->all_result_relids, toRemove->relid, toKeep->relid);
adjust_relid_set(root->leaf_result_relids, toRemove->relid, toKeep->relid);
@ -2046,10 +1919,8 @@ split_selfjoin_quals(PlannerInfo *root, List *joinquals, List **selfjoinquals,
* when we have cast of the same var to different (but compatible)
* types.
*/
ChangeVarNodesExtended(rightexpr,
bms_singleton_member(rinfo->right_relids),
bms_singleton_member(rinfo->left_relids), 0,
replace_relid_callback);
ChangeVarNodes(rightexpr, bms_singleton_member(rinfo->right_relids),
bms_singleton_member(rinfo->left_relids), 0);
if (equal(leftexpr, rightexpr))
sjoinquals = lappend(sjoinquals, rinfo);
@ -2085,8 +1956,7 @@ match_unique_clauses(PlannerInfo *root, RelOptInfo *outer, List *uclauses,
bms_is_empty(rinfo->right_relids));
clause = (Expr *) copyObject(rinfo->clause);
ChangeVarNodesExtended((Node *) clause, relid, outer->relid, 0,
replace_relid_callback);
ChangeVarNodes((Node *) clause, relid, outer->relid, 0);
iclause = bms_is_empty(rinfo->left_relids) ? get_rightop(clause) :
get_leftop(clause);

138
src/backend/rewrite/rewriteManip.c
Unescape View File

@ -550,15 +550,19 @@ offset_relid_set(Relids relids, int offset)
* earlier to ensure that no unwanted side-effects occur!
*/
typedef struct
{
int rt_index;
int new_index;
int sublevels_up;
bool change_RangeTblRef;
} ChangeVarNodes_context;
static bool
ChangeVarNodes_walker(Node *node, ChangeVarNodes_context *context)
{
if (node == NULL)
return false;
if (context->callback && context->callback(node, context))
return false;
if (IsA(node, Var))
{
Var *var = (Var *) node;
@ -584,7 +588,7 @@ ChangeVarNodes_walker(Node *node, ChangeVarNodes_context *context)
cexpr->cvarno = context->new_index;
return false;
}
if (IsA(node, RangeTblRef))
if (IsA(node, RangeTblRef) && context->change_RangeTblRef)
{
RangeTblRef *rtr = (RangeTblRef *) node;
@ -631,6 +635,95 @@ ChangeVarNodes_walker(Node *node, ChangeVarNodes_context *context)
}
return false;
}
if (IsA(node, RestrictInfo))
{
RestrictInfo *rinfo = (RestrictInfo *) node;
int relid = -1;
bool is_req_equal =
(rinfo->required_relids == rinfo->clause_relids);
bool clause_relids_is_multiple =
(bms_membership(rinfo->clause_relids) == BMS_MULTIPLE);
/*
* Recurse down into clauses if the target relation is present in
* clause_relids or required_relids. We must check required_relids
* because the relation not present in clause_relids might still be
* present somewhere in orclause.
*/
if (bms_is_member(context->rt_index, rinfo->clause_relids) ||
bms_is_member(context->rt_index, rinfo->required_relids))
{
Relids new_clause_relids;
expression_tree_walker((Node *) rinfo->clause, ChangeVarNodes_walker, (void *) context);
expression_tree_walker((Node *) rinfo->orclause, ChangeVarNodes_walker, (void *) context);
new_clause_relids = adjust_relid_set(rinfo->clause_relids,
context->rt_index,
context->new_index);
/*
* Incrementally adjust num_base_rels based on the change of
* clause_relids, which could contain both base relids and
* outer-join relids. This operation is legal until we remove
* only baserels.
*/
rinfo->num_base_rels -= bms_num_members(rinfo->clause_relids) -
bms_num_members(new_clause_relids);
rinfo->clause_relids = new_clause_relids;
rinfo->left_relids =
adjust_relid_set(rinfo->left_relids, context->rt_index, context->new_index);
rinfo->right_relids =
adjust_relid_set(rinfo->right_relids, context->rt_index, context->new_index);
}
if (is_req_equal)
rinfo->required_relids = rinfo->clause_relids;
else
rinfo->required_relids =
adjust_relid_set(rinfo->required_relids, context->rt_index, context->new_index);
rinfo->outer_relids =
adjust_relid_set(rinfo->outer_relids, context->rt_index, context->new_index);
rinfo->incompatible_relids =
adjust_relid_set(rinfo->incompatible_relids, context->rt_index, context->new_index);
if (rinfo->mergeopfamilies &&
bms_get_singleton_member(rinfo->clause_relids, &relid) &&
clause_relids_is_multiple &&
relid == context->new_index && IsA(rinfo->clause, OpExpr))
{
Expr *leftOp;
Expr *rightOp;
leftOp = (Expr *) get_leftop(rinfo->clause);
rightOp = (Expr *) get_rightop(rinfo->clause);
/*
* For self-join elimination, changing varnos could transform
* "t1.a = t2.a" into "t1.a = t1.a". That is always true as long
* as "t1.a" is not null. We use qual() to check for such a case,
* and then we replace the qual for a check for not null
* (NullTest).
*/
if (leftOp != NULL && equal(leftOp, rightOp))
{
NullTest *ntest = makeNode(NullTest);
ntest->arg = leftOp;
ntest->nulltesttype = IS_NOT_NULL;
ntest->argisrow = false;
ntest->location = -1;
rinfo->clause = (Expr *) ntest;
rinfo->mergeopfamilies = NIL;
rinfo->left_em = NULL;
rinfo->right_em = NULL;
}
Assert(rinfo->orclause == NULL);
}
return false;
}
if (IsA(node, AppendRelInfo))
{
AppendRelInfo *appinfo = (AppendRelInfo *) node;
@ -664,28 +757,26 @@ ChangeVarNodes_walker(Node *node, ChangeVarNodes_context *context)
}
/*
* ChangeVarNodesExtended - similar to ChangeVarNodes, but with an additional
* 'callback' param
* ChangeVarNodesExtended - similar to ChangeVarNodes, but has additional
* 'change_RangeTblRef' param
*
* ChangeVarNodes changes a given node and all of its underlying nodes.
* This version of function additionally takes a callback, which has a
* chance to process a node before ChangeVarNodes_walker. A callback
* returns a boolean value indicating if given node should be skipped from
* further processing by ChangeVarNodes_walker. The callback is called
* only for expressions and other children nodes of a Query processed by
* a walker. Initial processing of the root Query doesn't involve the
* callback.
* However, self-join elimination (SJE) needs to skip the RangeTblRef node
* type. During SJE's last step, remove_rel_from_joinlist() removes
* remaining RangeTblRefs with target relid. If ChangeVarNodes() replaces
* the target relid before, remove_rel_from_joinlist() fails to identify
* the nodes to delete.
*/
void
ChangeVarNodesExtended(Node *node, int rt_index, int new_index,
int sublevels_up, ChangeVarNodes_callback callback)
int sublevels_up, bool change_RangeTblRef)
{
ChangeVarNodes_context context;
context.rt_index = rt_index;
context.new_index = new_index;
context.sublevels_up = sublevels_up;
context.callback = callback;
context.change_RangeTblRef = change_RangeTblRef;
/*
* Must be prepared to start with a Query or a bare expression tree; if
@ -735,20 +826,7 @@ ChangeVarNodesExtended(Node *node, int rt_index, int new_index,
void
ChangeVarNodes(Node *node, int rt_index, int new_index, int sublevels_up)
{
ChangeVarNodesExtended(node, rt_index, new_index, sublevels_up, NULL);
}
/*
* ChangeVarNodesWalkExpression - process expression within the custom
* callback provided to the
* ChangeVarNodesExtended.
*/
bool
ChangeVarNodesWalkExpression(Node *node, ChangeVarNodes_context *context)
{
return expression_tree_walker(node,
ChangeVarNodes_walker,
(void *) context);
ChangeVarNodesExtended(node, rt_index, new_index, sublevels_up, true);
}
/*

17
src/include/rewrite/rewriteManip.h
Unescape View File

@ -41,18 +41,6 @@ typedef enum ReplaceVarsNoMatchOption
REPLACEVARS_SUBSTITUTE_NULL, /* replace with a NULL Const */
} ReplaceVarsNoMatchOption;
typedef struct ChangeVarNodes_context ChangeVarNodes_context;
typedef bool (*ChangeVarNodes_callback) (Node *node,
ChangeVarNodes_context *arg);
struct ChangeVarNodes_context
{
int rt_index;
int new_index;
int sublevels_up;
ChangeVarNodes_callback callback;
};
extern Relids adjust_relid_set(Relids relids, int oldrelid, int newrelid);
extern void CombineRangeTables(List **dst_rtable, List **dst_perminfos,
@ -61,10 +49,7 @@ extern void OffsetVarNodes(Node *node, int offset, int sublevels_up);
extern void ChangeVarNodes(Node *node, int rt_index, int new_index,
int sublevels_up);
extern void ChangeVarNodesExtended(Node *node, int rt_index, int new_index,
int sublevels_up,
ChangeVarNodes_callback callback);
extern bool ChangeVarNodesWalkExpression(Node *node,
ChangeVarNodes_context *context);
int sublevels_up, bool change_RangeTblRef);
extern void IncrementVarSublevelsUp(Node *node, int delta_sublevels_up,
int min_sublevels_up);
extern void IncrementVarSublevelsUp_rtable(List *rtable,

1
src/tools/pgindent/typedefs.list
Unescape View File

@ -410,7 +410,6 @@ CatCacheHeader
CatalogId
CatalogIdMapEntry
CatalogIndexState
ChangeVarNodes_callback
ChangeVarNodes_context
CheckPoint
CheckPointStmt

Write Preview
Loading…
Cancel
Save