Commit 93bac51e authored by Evgeny Potemkin's avatar Evgeny Potemkin

Bug#45266: Uninitialized variable lead to an empty result.

The TABLE::reginfo.impossible_range is used by the optimizer to indicate
that the condition applied to the table is impossible. It wasn't initialized
at table opening and this might lead to an empty result on complex queries:
a query might set the impossible_range flag on a table and when the query finishes,
all tables are returned back to the table cache. The next query that uses the table
with the impossible_range flag set and an index over the table will see the flag
and thus return an empty result.

The open_table function now initializes the TABLE::reginfo.impossible_range
variable.

mysql-test/r/select.result:
  A test case for the bug#45266: Uninitialized variable lead to an empty result.
mysql-test/t/select.test:
  A test case for the bug#45266: Uninitialized variable lead to an empty result.
sql/sql_base.cc:
  Bug#45266: Uninitialized variable lead to an empty result.
  The open_table function now initializes the TABLE::reginfo.impossible_range
  variable.
sql/sql_select.cc:
  Bug#45266: Uninitialized variable lead to an empty result.
  The open_table function now initializes the TABLE::reginfo.impossible_range
  variable.
sql/structs.h:
  Bug#45266: Uninitialized variable lead to an empty result.
  A comment is added.
parent 59947ae6
...@@ -4457,4 +4457,83 @@ id select_type table type possible_keys key key_len ref rows filtered Extra ...@@ -4457,4 +4457,83 @@ id select_type table type possible_keys key key_len ref rows filtered Extra
Warnings: Warnings:
Note 1003 select '0' AS `a`,'0' AS `b`,'0' AS `c` from `test`.`t1` where 1 Note 1003 select '0' AS `a`,'0' AS `b`,'0' AS `c` from `test`.`t1` where 1
DROP TABLE t1; DROP TABLE t1;
#
# Bug#45266: Uninitialized variable lead to an empty result.
#
drop table if exists A,AA,B,BB;
CREATE TABLE `A` (
`pk` int(11) NOT NULL AUTO_INCREMENT,
`date_key` date NOT NULL,
`date_nokey` date NOT NULL,
`datetime_key` datetime NOT NULL,
`int_nokey` int(11) NOT NULL,
`time_key` time NOT NULL,
`time_nokey` time NOT NULL,
PRIMARY KEY (`pk`),
KEY `date_key` (`date_key`),
KEY `time_key` (`time_key`),
KEY `datetime_key` (`datetime_key`)
);
CREATE TABLE `AA` (
`pk` int(11) NOT NULL AUTO_INCREMENT,
`int_nokey` int(11) NOT NULL,
`time_key` time NOT NULL,
KEY `time_key` (`time_key`),
PRIMARY KEY (`pk`)
);
CREATE TABLE `B` (
`date_nokey` date NOT NULL,
`date_key` date NOT NULL,
`time_key` time NOT NULL,
`datetime_nokey` datetime NOT NULL,
`varchar_key` varchar(1) NOT NULL,
KEY `date_key` (`date_key`),
KEY `time_key` (`time_key`),
KEY `varchar_key` (`varchar_key`)
);
INSERT INTO `B` VALUES ('2003-07-28','2003-07-28','15:13:38','0000-00-00 00:00:00','f'),('0000-00-00','0000-00-00','00:05:48','2004-07-02 14:34:13','x');
CREATE TABLE `BB` (
`pk` int(11) NOT NULL AUTO_INCREMENT,
`int_nokey` int(11) NOT NULL,
`date_key` date NOT NULL,
`varchar_nokey` varchar(1) NOT NULL,
`date_nokey` date NOT NULL,
PRIMARY KEY (`pk`),
KEY `date_key` (`date_key`)
);
INSERT INTO `BB` VALUES (10,8,'0000-00-00','i','0000-00-00'),(11,0,'2005-08-18','','2005-08-18');
SELECT table1 . `pk` AS field1
FROM
(BB AS table1 INNER JOIN
(AA AS table2 STRAIGHT_JOIN A AS table3
ON ( table3 . `date_key` = table2 . `pk` ))
ON ( table3 . `datetime_key` = table2 . `int_nokey` ))
WHERE ( table3 . `date_key` <= 4 AND table2 . `pk` = table1 . `varchar_nokey`)
GROUP BY field1 ;
field1
SELECT table3 .`date_key` field1
FROM
B table1 LEFT JOIN B table3 JOIN
(BB table6 JOIN A table7 ON table6 .`varchar_nokey`)
ON table6 .`int_nokey` ON table6 .`date_key`
WHERE NOT ( table1 .`varchar_key` AND table7 .`pk`) GROUP BY field1;
field1
NULL
SELECT table4 . `time_nokey` AS field1 FROM
(AA AS table1 CROSS JOIN
(AA AS table2 STRAIGHT_JOIN
(B AS table3 STRAIGHT_JOIN A AS table4
ON ( table4 . `date_key` = table3 . `time_key` ))
ON ( table4 . `pk` = table3 . `date_nokey` ))
ON ( table4 . `time_key` = table3 . `datetime_nokey` ))
WHERE ( table4 . `time_key` < table1 . `time_key` AND
table1 . `int_nokey` != 'f')
GROUP BY field1 ORDER BY field1 , field1;
field1
SELECT table1 .`time_key` field2 FROM B table1 LEFT JOIN BB JOIN A table5 ON table5 .`date_nokey` ON table5 .`int_nokey` GROUP BY field2;
field2
00:05:48
15:13:38
drop table A,AA,B,BB;
#end of test for bug#45266
End of 5.1 tests End of 5.1 tests
...@@ -3799,4 +3799,90 @@ EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND a=a AND b=b) OR b > 20; ...@@ -3799,4 +3799,90 @@ EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND a=a AND b=b) OR b > 20;
EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND b=b AND a=a) OR b > 20; EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND b=b AND a=a) OR b > 20;
DROP TABLE t1; DROP TABLE t1;
--echo #
--echo # Bug#45266: Uninitialized variable lead to an empty result.
--echo #
--disable_warnings
drop table if exists A,AA,B,BB;
CREATE TABLE `A` (
`pk` int(11) NOT NULL AUTO_INCREMENT,
`date_key` date NOT NULL,
`date_nokey` date NOT NULL,
`datetime_key` datetime NOT NULL,
`int_nokey` int(11) NOT NULL,
`time_key` time NOT NULL,
`time_nokey` time NOT NULL,
PRIMARY KEY (`pk`),
KEY `date_key` (`date_key`),
KEY `time_key` (`time_key`),
KEY `datetime_key` (`datetime_key`)
);
CREATE TABLE `AA` (
`pk` int(11) NOT NULL AUTO_INCREMENT,
`int_nokey` int(11) NOT NULL,
`time_key` time NOT NULL,
KEY `time_key` (`time_key`),
PRIMARY KEY (`pk`)
);
CREATE TABLE `B` (
`date_nokey` date NOT NULL,
`date_key` date NOT NULL,
`time_key` time NOT NULL,
`datetime_nokey` datetime NOT NULL,
`varchar_key` varchar(1) NOT NULL,
KEY `date_key` (`date_key`),
KEY `time_key` (`time_key`),
KEY `varchar_key` (`varchar_key`)
);
INSERT INTO `B` VALUES ('2003-07-28','2003-07-28','15:13:38','0000-00-00 00:00:00','f'),('0000-00-00','0000-00-00','00:05:48','2004-07-02 14:34:13','x');
CREATE TABLE `BB` (
`pk` int(11) NOT NULL AUTO_INCREMENT,
`int_nokey` int(11) NOT NULL,
`date_key` date NOT NULL,
`varchar_nokey` varchar(1) NOT NULL,
`date_nokey` date NOT NULL,
PRIMARY KEY (`pk`),
KEY `date_key` (`date_key`)
);
INSERT INTO `BB` VALUES (10,8,'0000-00-00','i','0000-00-00'),(11,0,'2005-08-18','','2005-08-18');
# Test #1
SELECT table1 . `pk` AS field1
FROM
(BB AS table1 INNER JOIN
(AA AS table2 STRAIGHT_JOIN A AS table3
ON ( table3 . `date_key` = table2 . `pk` ))
ON ( table3 . `datetime_key` = table2 . `int_nokey` ))
WHERE ( table3 . `date_key` <= 4 AND table2 . `pk` = table1 . `varchar_nokey`)
GROUP BY field1 ;
SELECT table3 .`date_key` field1
FROM
B table1 LEFT JOIN B table3 JOIN
(BB table6 JOIN A table7 ON table6 .`varchar_nokey`)
ON table6 .`int_nokey` ON table6 .`date_key`
WHERE NOT ( table1 .`varchar_key` AND table7 .`pk`) GROUP BY field1;
# Test #2
SELECT table4 . `time_nokey` AS field1 FROM
(AA AS table1 CROSS JOIN
(AA AS table2 STRAIGHT_JOIN
(B AS table3 STRAIGHT_JOIN A AS table4
ON ( table4 . `date_key` = table3 . `time_key` ))
ON ( table4 . `pk` = table3 . `date_nokey` ))
ON ( table4 . `time_key` = table3 . `datetime_nokey` ))
WHERE ( table4 . `time_key` < table1 . `time_key` AND
table1 . `int_nokey` != 'f')
GROUP BY field1 ORDER BY field1 , field1;
SELECT table1 .`time_key` field2 FROM B table1 LEFT JOIN BB JOIN A table5 ON table5 .`date_nokey` ON table5 .`int_nokey` GROUP BY field2;
--enable_warnings
drop table A,AA,B,BB;
--echo #end of test for bug#45266
--echo End of 5.1 tests --echo End of 5.1 tests
...@@ -2963,6 +2963,7 @@ TABLE *open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root, ...@@ -2963,6 +2963,7 @@ TABLE *open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
table->insert_values= 0; table->insert_values= 0;
table->fulltext_searched= 0; table->fulltext_searched= 0;
table->file->ft_handler= 0; table->file->ft_handler= 0;
table->reginfo.impossible_range= 0;
/* Catch wrong handling of the auto_increment_field_not_null. */ /* Catch wrong handling of the auto_increment_field_not_null. */
DBUG_ASSERT(!table->auto_increment_field_not_null); DBUG_ASSERT(!table->auto_increment_field_not_null);
table->auto_increment_field_not_null= FALSE; table->auto_increment_field_not_null= FALSE;
......
...@@ -2432,7 +2432,6 @@ static ha_rows get_quick_record_count(THD *thd, SQL_SELECT *select, ...@@ -2432,7 +2432,6 @@ static ha_rows get_quick_record_count(THD *thd, SQL_SELECT *select,
if (select) if (select)
{ {
select->head=table; select->head=table;
table->reginfo.impossible_range=0;
if ((error= select->test_quick_select(thd, *(key_map *)keys,(table_map) 0, if ((error= select->test_quick_select(thd, *(key_map *)keys,(table_map) 0,
limit, 0)) == 1) limit, 0)) == 1)
DBUG_RETURN(select->quick->records); DBUG_RETURN(select->quick->records);
......
...@@ -107,6 +107,10 @@ typedef struct st_reginfo { /* Extra info about reg */ ...@@ -107,6 +107,10 @@ typedef struct st_reginfo { /* Extra info about reg */
struct st_join_table *join_tab; /* Used by SELECT() */ struct st_join_table *join_tab; /* Used by SELECT() */
enum thr_lock_type lock_type; /* How database is used */ enum thr_lock_type lock_type; /* How database is used */
bool not_exists_optimize; bool not_exists_optimize;
/*
TRUE <=> range optimizer found that there is no rows satisfying
table conditions.
*/
bool impossible_range; bool impossible_range;
} REGINFO; } REGINFO;
......
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