mirror of
				https://github.com/MariaDB/server.git
				synced 2025-10-31 02:46:29 +01:00 
			
		
		
		
	 192427e37d
			
		
	
	
	192427e37d
	
	
	
		
			
			There was a bug in JOIN::make_notnull_conds_for_range_scans() when clearing TABLE->tmp_set, which was used to mark fields that could not be null. This function was only used if 'not_null_range_scan=on' is set. The effect was that tmp_set contained a 'random value' and this caused the optimizer to think that some fields could not be null. FLUSH TABLES clears tmp_set and because of this things worked temporarily. Fixed by clearing tmp_set properly.
		
			
				
	
	
		
			76 lines
		
	
	
	
		
			2.5 KiB
		
	
	
	
		
			Text
		
	
	
	
	
	
			
		
		
	
	
			76 lines
		
	
	
	
		
			2.5 KiB
		
	
	
	
		
			Text
		
	
	
	
	
	
| drop table if exists t1;
 | |
| create table t1 (nr int(5) not null auto_increment,b blob,str char(10), primary key (nr));
 | |
| select count(*) from t1;
 | |
| count(*)
 | |
| 0
 | |
| select * from t1;
 | |
| nr	b	str
 | |
| select * from t1 limit 0;
 | |
| nr	b	str
 | |
| show status like "Empty_queries";
 | |
| Variable_name	Value
 | |
| Empty_queries	2
 | |
| drop table t1;
 | |
| select * from t2;
 | |
| ERROR 42S02: Table 'test.t2' doesn't exist
 | |
| show status like "Empty_queries";
 | |
| Variable_name	Value
 | |
| Empty_queries	2
 | |
| # End of 4.1 tests
 | |
| #
 | |
| # MDEV-30333 Wrong result with not_null_range_scan and LEFT JOIN with empty table
 | |
| #
 | |
| set @save_optimizer_switch=@@optimizer_switch;
 | |
| CREATE TABLE t1 (a INT, b INT) ENGINE=MyISAM;
 | |
| INSERT INTO t1 (b) VALUES (1),(2);
 | |
| CREATE TABLE t2 (c INT) ENGINE=MyISAM;
 | |
| SET optimizer_switch= 'not_null_range_scan=off';
 | |
| explain extended SELECT b FROM t1 LEFT JOIN t2 ON t2.c = a WHERE a IS NULL ORDER BY b;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 | |
| 1	SIMPLE	t2	system	NULL	NULL	NULL	NULL	0	0.00	Const row not found
 | |
| 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where; Using filesort
 | |
| Warnings:
 | |
| Note	1003	select `test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`a` is null order by `test`.`t1`.`b`
 | |
| SELECT b FROM t1 LEFT JOIN t2 ON t2.c = a WHERE a IS NULL ORDER BY b;
 | |
| b
 | |
| 1
 | |
| 2
 | |
| SET optimizer_switch = 'not_null_range_scan=on';
 | |
| explain extended SELECT b FROM t1 LEFT JOIN t2 ON t2.c = a WHERE a IS NULL ORDER BY b;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 | |
| 1	SIMPLE	t2	system	NULL	NULL	NULL	NULL	0	0.00	Const row not found
 | |
| 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where; Using filesort
 | |
| Warnings:
 | |
| Note	1003	select `test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`a` is null order by `test`.`t1`.`b`
 | |
| SELECT b FROM t1 LEFT JOIN t2 ON t2.c = a WHERE a IS NULL ORDER BY b;
 | |
| b
 | |
| 1
 | |
| 2
 | |
| flush tables;
 | |
| SELECT b FROM t1 LEFT JOIN t2 ON t2.c = a WHERE a IS NULL ORDER BY b;
 | |
| b
 | |
| 1
 | |
| 2
 | |
| drop table t1,t2;
 | |
| # Second test in MDEV-30333
 | |
| CREATE TABLE t1 (a int, b varchar(10)) ENGINE=MyISAM;
 | |
| INSERT INTO t1 VALUES (69,'foo'),(71,'bar');
 | |
| CREATE TABLE t2 (c int) ENGINE=MyISAM;
 | |
| INSERT INTO t2 VALUES (1),(2);
 | |
| CREATE TABLE t3 (d int, e int, KEY(e)) ENGINE=MyISAM;
 | |
| SELECT * FROM t1 LEFT JOIN t2 LEFT JOIN t3 ON t3.e = t3.d ON 1;
 | |
| a	b	c	d	e
 | |
| 69	foo	1	NULL	NULL
 | |
| 71	bar	1	NULL	NULL
 | |
| 69	foo	2	NULL	NULL
 | |
| 71	bar	2	NULL	NULL
 | |
| SET optimizer_switch = 'not_null_range_scan=on';
 | |
| SELECT * FROM t1 LEFT JOIN t2 LEFT JOIN t3 ON t3.e = t3.d ON 1;
 | |
| a	b	c	d	e
 | |
| 69	foo	1	NULL	NULL
 | |
| 71	bar	1	NULL	NULL
 | |
| 69	foo	2	NULL	NULL
 | |
| 71	bar	2	NULL	NULL
 | |
| DROP TABLE t1, t2, t3;
 | |
| set @@optimizer_switch=@save_optimizer_switch;
 | |
| End of 10.5 tests
 |