Changeset: 66099b3f3afd for MonetDB
URL: https://dev.monetdb.org/hg/MonetDB?cmd=changeset;node=66099b3f3afd
Modified Files:
sql/server/rel_optimizer.c
sql/server/rel_optimizer.h
sql/server/rel_unnest.c
sql/test/BugTracker-2015/Tests/crash.Bug-3736.stable.out
sql/test/BugTracker/Tests/bug_in_selection.SF-1892413.stable.out
Branch: default
Log Message:
improved handling of unnesting, ie don't introduce an intermediate in the
general unnesting case when left already has unique/distinct values
diffs (truncated from 337 to 300 lines):
diff --git a/sql/server/rel_optimizer.c b/sql/server/rel_optimizer.c
--- a/sql/server/rel_optimizer.c
+++ b/sql/server/rel_optimizer.c
@@ -41,24 +41,6 @@ static sql_rel * rel_remove_empty_select
static sql_subfunc *find_func( mvc *sql, char *name, list *exps );
-static int
-exps_unique( list *exps )
-{
- node *n;
-
- if ((n = exps->h) != NULL) {
- sql_exp *e = n->data;
- prop *p;
-
- if (e && (p = find_prop(e->p, PROP_HASHCOL)) != NULL) {
- sql_ukey *k = p->value;
- if (k && list_length(k->k.columns) <= 1)
- return 1;
- }
- }
- return 0;
-}
-
/* The important task of the relational optimizer is to optimize the
join order.
@@ -130,10 +112,11 @@ name_find_column( sql_rel *rel, const ch
case op_left:
case op_right:
case op_full:
+ /* first right (possible subquery) */
+ c = name_find_column( rel->r, rname, name, pnr, bt);
+ /* fall through */
case op_semi:
case op_anti:
- /* first right (possible subquery) */
- c = name_find_column( rel->r, rname, name, pnr, bt);
if (!c)
c = name_find_column( rel->l, rname, name, pnr, bt);
return c;
@@ -2398,6 +2381,81 @@ exp_push_down_prj(mvc *sql, sql_exp *e,
return NULL;
}
+static int
+rel_is_unique( sql_rel *rel, sql_ukey *k)
+{
+ switch(rel->op) {
+ case op_left:
+ case op_right:
+ case op_full:
+ case op_join:
+ return 0;
+ case op_semi:
+ case op_anti:
+ return rel_is_unique(rel->l, k);
+ case op_table:
+ case op_basetable:
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+int
+exps_unique(mvc *sql, sql_rel *rel, list *exps)
+{
+ node *n;
+ char *matched = NULL;
+ int nr = 0;
+ sql_ukey *k = NULL;
+
+ if (list_empty(exps))
+ return 0;
+ for(n = exps->h; n && !k; n = n->next) {
+ sql_exp *e = n->data;
+ prop *p;
+
+ if (e && (p = find_prop(e->p, PROP_HASHCOL)) != NULL)
+ k = p->value;
+ }
+ if (!k || list_length(k->k.columns) > list_length(exps))
+ return 0;
+ if (rel) {
+ matched = (char*)sa_alloc(sql->sa, list_length(k->k.columns));
+ memset(matched, 0, list_length(k->k.columns));
+ for(n = exps->h; n; n = n->next) {
+ sql_exp *e = n->data;
+ fcmp cmp = (fcmp)&kc_column_cmp;
+ sql_column *c = exp_find_column(rel, e, -2);
+ node *m;
+
+ if (c && (m=list_find(k->k.columns, c, cmp)) != NULL) {
+ int pos = list_position(k->k.columns, m->data);
+ if (!matched[pos])
+ nr++;
+ matched[pos] = 1;
+ }
+ }
+ if (nr == list_length(k->k.columns)) {
+ return rel_is_unique(rel, k);
+ }
+ }
+ /*
+ if ((n = exps->h) != NULL) {
+ sql_exp *e = n->data;
+ prop *p;
+
+ if (e && (p = find_prop(e->p, PROP_HASHCOL)) != NULL) {
+ sql_ukey *k = p->value;
+ if (k && list_length(k->k.columns) <= 1)
+ return 1;
+ }
+ }
+ */
+ return 0;
+}
+
+
static sql_rel *
rel_distinct_project2groupby(int *changes, mvc *sql, sql_rel *rel)
{
@@ -2411,9 +2469,9 @@ rel_distinct_project2groupby(int *change
}
/* rewrite distinct project [ pk ] ( select ( table ) [ e op val ])
- * into project [ pk ] ( select ( table ) */
+ * into project [ pk ] ( select/semijoin ( table ) */
if (rel->op == op_project && rel->l && !rel->r /* no order by */ &&
need_distinct(rel) &&
- l->op == op_select && exps_unique(rel->exps))
+ (l->op == op_select || l->op == op_semi) && exps_unique(sql, rel,
rel->exps))
set_nodistinct(rel);
/* rewrite distinct project [ gbe ] ( select ( groupby [ gbe ] [ gbe, e
] )[ e op val ])
* into project [ gbe ] ( select ( group etc ) */
@@ -5173,7 +5231,7 @@ static sql_rel *
rel_push_project_down_union(int *changes, mvc *sql, sql_rel *rel)
{
/* first remove distinct if already unique */
- if (rel->op == op_project && need_distinct(rel) && rel->exps &&
exps_unique(rel->exps))
+ if (rel->op == op_project && need_distinct(rel) && rel->exps &&
exps_unique(sql, rel, rel->exps))
set_nodistinct(rel);
if (rel->op == op_project && rel->l && rel->exps && !rel->r) {
@@ -5201,8 +5259,8 @@ rel_push_project_down_union(int *changes
ur = rel_project(sql->sa, ur,
rel_projections(sql, ur, NULL, 1, 1));
need_distinct = (need_distinct &&
- (!exps_unique(ul->exps) ||
- !exps_unique(ur->exps)));
+ (!exps_unique(sql, ul, ul->exps) ||
+ !exps_unique(sql, ur, ur->exps)));
rel_rename_exps(sql, u->exps, ul->exps);
rel_rename_exps(sql, u->exps, ur->exps);
@@ -5588,7 +5646,7 @@ rel_groupby_distinct(int *changes, mvc *
if (exp_aggr_is_count(e) && need_distinct(e)) {
/* if count over unique values (ukey/pkey) */
- if (e->l && exps_unique(e->l))
+ if (e->l && exps_unique(sql, rel, e->l))
set_nodistinct(e);
}
}
diff --git a/sql/server/rel_optimizer.h b/sql/server/rel_optimizer.h
--- a/sql/server/rel_optimizer.h
+++ b/sql/server/rel_optimizer.h
@@ -17,6 +17,7 @@ extern sql_rel * rel_optimizer(mvc *sql,
extern int exp_joins_rels(sql_exp *e, list *rels);
extern void *name_find_column( sql_rel *rel, const char *rname, const char
*name, int pnr, sql_rel **bt );
+extern int exps_unique(mvc *sql, sql_rel *rel, list *exps);
extern sql_rel * rel_dce(mvc *sql, sql_rel *rel);
diff --git a/sql/server/rel_unnest.c b/sql/server/rel_unnest.c
--- a/sql/server/rel_unnest.c
+++ b/sql/server/rel_unnest.c
@@ -10,11 +10,22 @@
#include "monetdb_config.h"
#include "rel_unnest.h"
+#include "rel_optimizer.h"
+#include "rel_prop.h"
#include "rel_rel.h"
#include "rel_exp.h"
static int exps_have_freevar( list *exps );
+/* check if the set is distinct for the set of free variables */
+static int
+is_distinct_set(mvc *sql, sql_rel *rel, list *ad)
+{
+ if (ad && exps_unique(sql, rel, ad ))
+ return 1;
+ return need_distinct(rel);
+}
+
int
exp_has_freevar( sql_exp *e)
{
@@ -483,19 +494,23 @@ exps_is_constant( list *exps )
}
static sql_rel *
-push_up_groupby(mvc *sql, sql_rel *rel)
+push_up_groupby(mvc *sql, sql_rel *rel, list *ad)
{
/* input rel is dependent join with on the right a project */
if (rel && (is_join(rel->op) || is_semi(rel->op)) && is_dependent(rel))
{
sql_rel *l = rel->l, *r = rel->r;
/* left of rel should be a set */
- if (l && need_distinct(l) && r && r->op == op_groupby) {
+ if (l && is_distinct_set(sql, l, ad) && r && r->op ==
op_groupby) {
list *sexps, *jexps;
node *n;
/* move groupby up, ie add attributes of left + the old
expression list */
list *a = rel_projections(sql, rel->l, NULL, 1, 1);
+ assert(rel->op != op_anti);
+ if (rel->op == op_semi && !need_distinct(l))
+ rel->op = op_join;
+
for (n = r->exps->h; n; n = n->next ) {
sql_exp *e = n->data;
@@ -611,7 +626,7 @@ push_up_join(mvc *sql, sql_rel *rel)
sql_rel *d = rel->l, *j = rel->r;
/* left of rel should be a set */
- if (d && need_distinct(d) && j && (is_join(j->op) ||
is_semi(j->op))) {
+ if (d && is_distinct_set(sql, d, NULL) && j && (is_join(j->op)
|| is_semi(j->op))) {
sql_rel *jl = j->l, *jr = j->r;
/* op_join if F(jl) intersect A(D) = empty -> jl join
(D djoin jr)
* F(jr) intersect A(D) = empty -> (D djoin
jl) join jr
@@ -688,7 +703,7 @@ push_up_set(mvc *sql, sql_rel *rel)
sql_rel *d = rel->l, *s = rel->r;
/* left of rel should be a set */
- if (d && need_distinct(d) && s && is_set(s->op)) {
+ if (d && is_distinct_set(sql, d, NULL) && s && is_set(s->op)) {
list *sexps;
node *m;
sql_rel *sl = s->l, *sr = s->r, *n;
@@ -721,7 +736,7 @@ push_up_table(mvc *sql, sql_rel *rel)
sql_rel *d = rel->l, *tf = rel->r;
/* for now just push d into function */
- if (d && need_distinct(d) && tf && is_base(tf->op)) {
+ if (d && is_distinct_set(sql, d, NULL) && tf &&
is_base(tf->op)) {
if (tf->l) {
sql_rel *l = tf->l;
@@ -842,7 +857,7 @@ rel_unnest_dependent(mvc *sql, sql_rel *
/* try to push dependent join down */
if (rel_has_freevar(r)){
- list *ad;
+ list *ad = rel_dependent_var(sql, rel->l, rel->r);
if (r && is_simple_project(r->op)) {
rel = push_up_project(sql, rel);
@@ -859,22 +874,22 @@ rel_unnest_dependent(mvc *sql, sql_rel *
return rel_unnest_dependent(sql, rel);
}
- if (r && is_groupby(r->op) && need_distinct(l)) {
- rel = push_up_groupby(sql, rel);
+ if (r && is_groupby(r->op) && is_distinct_set(sql, l,
ad)) {
+ rel = push_up_groupby(sql, rel, ad);
return rel_unnest_dependent(sql, rel);
}
- if (r && (is_join(r->op) || is_semi(r->op)) &&
need_distinct(l)) {
+ if (r && (is_join(r->op) || is_semi(r->op)) &&
is_distinct_set(sql, l, NULL)) {
rel = push_up_join(sql, rel);
return rel_unnest_dependent(sql, rel);
}
- if (r && is_set(r->op) && need_distinct(l)) {
+ if (r && is_set(r->op) && is_distinct_set(sql, l,
NULL)) {
rel = push_up_set(sql, rel);
return rel_unnest_dependent(sql, rel);
}
- if (r && is_base(r->op) && need_distinct(l)) { /* TODO
table functions need dependent implementation */
+ if (r && is_base(r->op) && is_distinct_set(sql, l,
NULL)) { /* TODO table functions need dependent implementation */
rel = push_up_table(sql, rel);
return rel;
}
diff --git a/sql/test/BugTracker-2015/Tests/crash.Bug-3736.stable.out
b/sql/test/BugTracker-2015/Tests/crash.Bug-3736.stable.out
--- a/sql/test/BugTracker-2015/Tests/crash.Bug-3736.stable.out
+++ b/sql/test/BugTracker-2015/Tests/crash.Bug-3736.stable.out
@@ -98,10 +98,10 @@ project (
| | | | | | | & REF 2
| | | | | | ) [ "b3a"."open_auction_id" NOT NULL = "o"."open_auction_id" NOT
NULL ]
| | | | | ) [ "o"."open_auction_id" NOT NULL ] [ sys.min no nil ("b3a"."id"
NOT NULL HASHCOL ) NOT NULL as "L3"."L3", "o"."open_auction_id" NOT NULL ]
-| | | | ) [ "L3"."L3" NOT NULL, "o"."open_auction_id" NOT NULL as "L25"."L25" ]
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