Changeset: 480c1c2c0808 for MonetDB
URL: http://dev.monetdb.org/hg/MonetDB?cmd=changeset;node=480c1c2c0808
Modified Files:
sql/src/server/rel_optimizer.mx
sql/src/test/BugDay_2005-10-06_2.9.3/Tests/multiple_select_on_view.SF-935639.stable.out
sql/src/test/Tests/trace.stable.out
Branch: Jun2010
Log Message:
back ported improvement of rel_dce (fixes problem with
select count(*) from (select distinct x,y from a) as b
diffs (220 lines):
diff -r e42dc8f76d4c -r 480c1c2c0808 sql/src/server/rel_optimizer.mx
--- a/sql/src/server/rel_optimizer.mx Fri Jul 02 23:27:45 2010 +0200
+++ b/sql/src/server/rel_optimizer.mx Sun Jul 04 19:26:15 2010 +0200
@@ -2666,7 +2666,7 @@
return rel;
}
-static void
+static int
exp_mark_used(sql_rel *subrel, sql_exp *e)
{
sql_exp *ne = NULL;
@@ -2676,8 +2676,7 @@
ne = rel_find_exp(subrel, e);
break;
case e_convert:
- exp_mark_used(subrel, e->l);
- break;
+ return exp_mark_used(subrel, e->l);
case e_aggr:
case e_func: {
if (e->l) {
@@ -2717,23 +2716,52 @@
case e_atom:
/* atoms are used in e_cmp */
e->used = 1;
- break;
+ /* return 0 as constants may require a full column ! */
+ return 0;
}
- if (ne)
+ if (ne) {
ne->used = 1;
+ return ne->used;
+ }
+ return 0;
+}
+
+static void
+positional_exps_mark_used( sql_rel *rel, sql_rel *subrel )
+{
+ if (!rel->exps)
+ assert(0);
+
+ if (rel->exps && subrel->exps) {
+ node *n, *m;
+ for (n=rel->exps->h, m=subrel->exps->h; n && m; n = n->next, m
= m->next) {
+ sql_exp *e = n->data;
+ sql_exp *se = m->data;
+
+ if (e->used)
+ se->used = 1;
+ }
+ }
}
static void
exps_mark_used(sql_rel *rel, sql_rel *subrel)
{
+ int nr = 0;
if (rel->exps) {
node *n;
for (n=rel->exps->h; n; n = n->next) {
sql_exp *e = n->data;
- exp_mark_used(subrel, e);
+ if (!is_project(rel->op) || e->used)
+ nr += exp_mark_used(subrel, e);
}
}
+ /* for count/rank we need atleast one column */
+ if (!nr && (is_project(subrel->op) || is_base(subrel->op))) {
+ sql_exp *e = subrel->exps->h->data;
+ e->used = 1;
+ }
if (rel->r && (rel->op == op_project || rel->op == op_groupby)) {
list *l = rel->r;
node *n;
@@ -2765,7 +2793,7 @@
static void
rel_used(sql_rel *rel)
{
- if (is_join(rel->op) || is_union(rel->op)) {
+ if (is_join(rel->op) || is_set(rel->op)) {
if (rel->l)
rel_used(rel->l);
if (rel->r)
@@ -2783,6 +2811,10 @@
rel_mark_used(mvc *sql, sql_rel *rel, int proj)
{
(void)sql;
+
+ if (proj && (need_distinct(rel)))
+ rel_used(rel);
+
switch(rel->op) {
case op_basetable:
case op_table:
@@ -2824,10 +2856,17 @@
*
* Project part of union is based on column position.
*/
- if (proj) {
- /* properly mark left/right based on exps list */
- rel_used(rel->l);
- rel_used(rel->r);
+ if (proj && (need_distinct(rel) || !rel->exps)) {
+ rel_used(rel);
+ if (!rel->exps) {
+ rel_used(rel->l);
+ rel_used(rel->r);
+ }
+ rel_mark_used(sql, rel->l, 0);
+ rel_mark_used(sql, rel->r, 0);
+ } else if (proj && !need_distinct(rel)) {
+ positional_exps_mark_used(rel, rel->l);
+ positional_exps_mark_used(rel, rel->r);
rel_mark_used(sql, rel->l, 0);
rel_mark_used(sql, rel->r, 0);
}
@@ -2868,11 +2907,8 @@
if (e->used || is_intern(e))
append(exps, exp_dup(e));
}
- /* atleast one (needed for crossproducts, count(*),
rank() and single value projections) ! */
- if (list_length(exps) == 0) {
- sql_exp *e = rel->exps->h->data;
- append(exps, exp_dup(e));
- }
+ /* atleast one (needed for crossproducts, count(*),
rank() and single value projections) !, handled by exps_mark_used */
+ assert(list_length(exps) > 0);
list_destroy(rel->exps);
rel->exps = exps;
}
@@ -2887,6 +2923,10 @@
case op_project:
case op_groupby:
+ case op_union:
+ case op_inter:
+ case op_except:
+
if (rel->l && rel->exps) {
node *n;
list *exps = new_exp_list();
@@ -2897,11 +2937,8 @@
if (e->used || is_intern(e))
append(exps, exp_dup(e));
}
- /* atleast one (needed for crossproducts, count(*),
rank() and single value projections) ! */
- if (list_length(exps) == 0) {
- sql_exp *e = rel->exps->h->data;
- append(exps, exp_dup(e));
- }
+ /* atleast one (needed for crossproducts, count(*),
rank() and single value projections) !, handled by exps_mark_used */
+ assert(list_length(exps) > 0);
list_destroy(rel->exps);
rel->exps = exps;
}
@@ -2913,12 +2950,6 @@
case op_select:
- case op_union:
- case op_inter:
- case op_except:
- /* We cannot remove here as set projection are based on column
- position */
-
case op_join:
case op_left:
case op_right:
@@ -3012,9 +3043,13 @@
if (!rel)
return rel;
+ /*
+ * Mark used up until the next project
+ * For setops we need to first mark, then remove
+ * because of positional dependency
+ */
+ rel_mark_used(sql, rel, 1);
rel = rel_remove_unused(sql, rel);
- /* mark used up until the next project */
- rel_mark_used(sql, rel, 1);
rel_dce_down(sql, rel, 1);
return rel;
}
diff -r e42dc8f76d4c -r 480c1c2c0808
sql/src/test/BugDay_2005-10-06_2.9.3/Tests/multiple_select_on_view.SF-935639.stable.out
---
a/sql/src/test/BugDay_2005-10-06_2.9.3/Tests/multiple_select_on_view.SF-935639.stable.out
Fri Jul 02 23:27:45 2010 +0200
+++
b/sql/src/test/BugDay_2005-10-06_2.9.3/Tests/multiple_select_on_view.SF-935639.stable.out
Sun Jul 04 19:26:15 2010 +0200
@@ -26,12 +26,14 @@
[ 1 ]
[ 1 ]
-% sys.a # table_name
+#select count(*) from c;
+% sys.c # table_name
% L2 # name
% wrd # type
% 1 # length
[ 2 ]
-% sys.a # table_name
+#select count(*) from c;
+% sys.c # table_name
% L3 # name
% wrd # type
% 1 # length
diff -r e42dc8f76d4c -r 480c1c2c0808 sql/src/test/Tests/trace.stable.out
--- a/sql/src/test/Tests/trace.stable.out Fri Jul 02 23:27:45 2010 +0200
+++ b/sql/src/test/Tests/trace.stable.out Sun Jul 04 19:26:15 2010 +0200
@@ -35,7 +35,7 @@
% L2 # name
% wrd # type
% 2 # length
-[ 47 ]
+[ 42 ]
# 11:14:41 >
# 11:14:41 > Done.
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