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nexedi
MariaDB
Commits
503731d8
Commit
503731d8
authored
Apr 05, 2013
by
Igor Babaev
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Fixed bug mdev-4371.
Avoid possible division by 0.
parent
daaa5834
Changes
4
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4 changed files
with
91 additions
and
1 deletion
+91
-1
mysql-test/r/selectivity.result
mysql-test/r/selectivity.result
+28
-0
mysql-test/r/selectivity_innodb.result
mysql-test/r/selectivity_innodb.result
+29
-0
mysql-test/t/selectivity.test
mysql-test/t/selectivity.test
+33
-0
sql/sql_select.cc
sql/sql_select.cc
+1
-1
No files found.
mysql-test/r/selectivity.result
View file @
503731d8
...
...
@@ -822,4 +822,32 @@ DROP TABLE t1;
set histogram_size=@save_histogram_size;
set histogram_type=@save_histogram_type;
set use_stat_tables=@save_use_stat_tables;
#
# Bug mdev-4371: Join with condition supported by index on an empty table
# with optimizer_use_condition_selectivity=3
#
set use_stat_tables=PREFERABLY;
CREATE TABLE t1 (a int, b int, INDEX(a));
CREATE TABLE t2 (c int);
INSERT INTO t2 VALUES (1),(2),(3),(4),(5),(6),(7),(8);
ANALYZE TABLE t1, t2;
Table Op Msg_type Msg_text
test.t1 analyze status Table is already up to date
test.t2 analyze status OK
FLUSH TABLES;
set optimizer_use_condition_selectivity=3;
set @save_optimizer_switch=@@optimizer_switch;
set optimizer_switch='index_condition_pushdown=off';
EXPLAIN EXTENDED
SELECT * FROM t1, t2 WHERE a > 9;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
Warnings:
Note 1003 select NULL AS `a`,NULL AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t1` join `test`.`t2` where 0
SELECT * FROM t1, t2 WHERE a > 9;
a b c
set optimizer_switch=@save_optimizer_switch;
set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
DROP TABLE t1,t2;
set use_stat_tables=@save_use_stat_tables;
set use_stat_tables=@save_use_stat_tables;
mysql-test/r/selectivity_innodb.result
View file @
503731d8
...
...
@@ -829,6 +829,35 @@ DROP TABLE t1;
set histogram_size=@save_histogram_size;
set histogram_type=@save_histogram_type;
set use_stat_tables=@save_use_stat_tables;
#
# Bug mdev-4371: Join with condition supported by index on an empty table
# with optimizer_use_condition_selectivity=3
#
set use_stat_tables=PREFERABLY;
CREATE TABLE t1 (a int, b int, INDEX(a));
CREATE TABLE t2 (c int);
INSERT INTO t2 VALUES (1),(2),(3),(4),(5),(6),(7),(8);
ANALYZE TABLE t1, t2;
Table Op Msg_type Msg_text
test.t1 analyze status OK
test.t2 analyze status OK
FLUSH TABLES;
set optimizer_use_condition_selectivity=3;
set @save_optimizer_switch=@@optimizer_switch;
set optimizer_switch='index_condition_pushdown=off';
EXPLAIN EXTENDED
SELECT * FROM t1, t2 WHERE a > 9;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 range a a 5 NULL 1 0.00 Using where
1 SIMPLE t2 ALL NULL NULL NULL NULL 8 100.00 Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t1` join `test`.`t2` where (`test`.`t1`.`a` > 9)
SELECT * FROM t1, t2 WHERE a > 9;
a b c
set optimizer_switch=@save_optimizer_switch;
set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
DROP TABLE t1,t2;
set use_stat_tables=@save_use_stat_tables;
set use_stat_tables=@save_use_stat_tables;
set optimizer_switch=@save_optimizer_switch_for_selectivity_test;
SET SESSION STORAGE_ENGINE=DEFAULT;
mysql-test/t/selectivity.test
View file @
503731d8
...
...
@@ -412,4 +412,37 @@ set histogram_size=@save_histogram_size;
set
histogram_type
=@
save_histogram_type
;
set
use_stat_tables
=@
save_use_stat_tables
;
--
echo
#
--
echo
# Bug mdev-4371: Join with condition supported by index on an empty table
--
echo
# with optimizer_use_condition_selectivity=3
--
echo
#
set
use_stat_tables
=
PREFERABLY
;
CREATE
TABLE
t1
(
a
int
,
b
int
,
INDEX
(
a
));
CREATE
TABLE
t2
(
c
int
);
INSERT
INTO
t2
VALUES
(
1
),(
2
),(
3
),(
4
),(
5
),(
6
),(
7
),(
8
);
ANALYZE
TABLE
t1
,
t2
;
FLUSH
TABLES
;
set
optimizer_use_condition_selectivity
=
3
;
set
@
save_optimizer_switch
=@@
optimizer_switch
;
set
optimizer_switch
=
'index_condition_pushdown=off'
;
EXPLAIN
EXTENDED
SELECT
*
FROM
t1
,
t2
WHERE
a
>
9
;
SELECT
*
FROM
t1
,
t2
WHERE
a
>
9
;
set
optimizer_switch
=@
save_optimizer_switch
;
set
optimizer_use_condition_selectivity
=@
save_optimizer_use_condition_selectivity
;
DROP
TABLE
t1
,
t2
;
set
use_stat_tables
=@
save_use_stat_tables
;
set
use_stat_tables
=@
save_use_stat_tables
;
sql/sql_select.cc
View file @
503731d8
...
...
@@ -7030,7 +7030,7 @@ double table_cond_selectivity(JOIN *join, uint idx, JOIN_TAB *s,
/* Discount the selectivity of the access method used to join table s */
if
(
s
->
quick
&&
s
->
quick
->
index
!=
MAX_KEY
)
{
if
(
pos
->
key
==
0
)
if
(
pos
->
key
==
0
&&
table_records
>
0
)
{
sel
*=
table
->
quick_rows
[
s
->
quick
->
index
]
/
table_records
;
}
...
...
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