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	columns
Fixed confusing warning.
Quoting INSERT section of the manual:
----
Inserting NULL into a column that has been declared NOT NULL. For
multiple-row INSERT statements or INSERT INTO ... SELECT statements, the
column is set to the implicit default value for the column data type. This
is 0 for numeric types, the empty string ('') for string types, and the
"zero" value for date and time types. INSERT INTO ... SELECT statements are
handled the same way as multiple-row inserts because the server does not
examine the result set from the SELECT to see whether it returns a single
row. (For a single-row INSERT, no warning occurs when NULL is inserted into
a NOT NULL column. Instead, the statement fails with an error.)
----
This is also true for LOAD DATA INFILE. For INSERT user can specify
DEFAULT keyword as a value to set column default. There is no similiar
feature available for LOAD DATA INFILE.
mysql-test/r/auto_increment.result:
  Fixed confusing warning.
mysql-test/r/create.result:
  Fixed confusing warning.
mysql-test/r/insert.result:
  Fixed confusing warning.
mysql-test/r/insert_select.result:
  Fixed confusing warning.
mysql-test/r/key.result:
  Fixed confusing warning.
mysql-test/r/null.result:
  Fixed confusing warning.
mysql-test/r/null_key.result:
  Fixed confusing warning.
mysql-test/r/ps_2myisam.result:
  Fixed confusing warning.
mysql-test/r/ps_3innodb.result:
  Fixed confusing warning.
mysql-test/r/ps_4heap.result:
  Fixed confusing warning.
mysql-test/r/ps_5merge.result:
  Fixed confusing warning.
mysql-test/r/ps_6bdb.result:
  Fixed confusing warning.
mysql-test/r/strict.result:
  Fixed confusing warning.
mysql-test/r/view.result:
  Fixed confusing warning.
mysql-test/r/warnings.result:
  Fixed confusing warning.
sql/share/errmsg.txt:
  Fixed confusing warning.
		
	
		
			
				
	
	
		
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			432 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| drop table if exists t1,t2;
 | |
| create table t1 (a int, b int not null,unique key (a,b),index(b)) engine=myisam;
 | |
| insert ignore into t1 values (1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(null,7),(9,9),(8,8),(7,7),(null,9),(null,9),(6,6);
 | |
| explain select * from t1 where a is null;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ref	a	a	5	const	3	Using where; Using index
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| explain select * from t1 where a is null and b = 2;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ref	a,b	a	9	const,const	1	Using where; Using index
 | |
| explain select * from t1 where a is null and b = 7;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ref	a,b	a	9	const,const	1	Using where; Using index
 | |
| explain select * from t1 where a=2 and b = 2;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	const	a,b	a	9	const,const	1	Using index
 | |
| explain select * from t1 where a<=>b limit 2;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	index	NULL	a	9	NULL	12	Using where; Using index
 | |
| explain select * from t1 where (a is null or a > 0 and a < 3) and b < 5 limit 3;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	range	a,b	a	9	NULL	3	Using where; Using index
 | |
| explain select * from t1 where (a is null or a = 7) and b=7;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ref_or_null	a,b	a	9	const,const	2	Using where; Using index
 | |
| explain select * from t1 where (a is null or a = 7) and b=7 order by a;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ref_or_null	a,b	a	9	const,const	2	Using where; Using index; Using filesort
 | |
| explain select * from t1 where (a is null and b>a) or a is null and b=7 limit 2;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ref	a,b	a	5	const	3	Using where; Using index
 | |
| explain select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ref	a,b	a	5	const	2	Using where; Using index
 | |
| explain select * from t1 where a > 1 and a < 3 limit 1;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	range	a	a	5	NULL	1	Using where; Using index
 | |
| explain select * from t1 where a > 8 and a < 9;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	range	a	a	5	NULL	1	Using where; Using index
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| select * from t1 where a is null;
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| a	b
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| NULL	7
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| NULL	9
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| NULL	9
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| select * from t1 where a is null and b = 7;
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| a	b
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| NULL	7
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| select * from t1 where a<=>b limit 2;
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| a	b
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| 1	1
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| 2	2
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| select * from t1 where (a is null or a > 0 and a < 3) and b < 5 limit 3;
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| a	b
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| 1	1
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| 2	2
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| select * from t1 where (a is null or a > 0 and a < 3) and b > 7 limit 3;
 | |
| a	b
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| NULL	9
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| NULL	9
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| select * from t1 where (a is null or a = 7) and b=7;
 | |
| a	b
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| 7	7
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| NULL	7
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| select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
 | |
| a	b
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| NULL	7
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| NULL	9
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| NULL	9
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| select * from t1 where a > 1 and a < 3 limit 1;
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| a	b
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| 2	2
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| select * from t1 where a > 8 and a < 9;
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| a	b
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| create table t2 like t1;
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| insert into t2 select * from t1;
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| alter table t1 modify b blob not null, add c int not null, drop key a, add unique key (a,b(20),c), drop key b, add key (b(10));
 | |
| explain select * from t1 where a is null and b = 2;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ref	a,b	a	5	const	3	Using where
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| explain select * from t1 where a is null and b = 2 and c=0;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ref	a,b	a	5	const	3	Using where
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| explain select * from t1 where a is null and b = 7 and c=0;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ref	a,b	a	5	const	3	Using where
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| explain select * from t1 where a=2 and b = 2;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ref	a,b	a	5	const	1	Using where
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| explain select * from t1 where a<=>b limit 2;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	12	Using where
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| explain select * from t1 where (a is null or a > 0 and a < 3) and b < 5 and c=0 limit 3;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	range	a,b	a	5	NULL	5	Using where
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| explain select * from t1 where (a is null or a = 7) and b=7 and c=0;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	ref_or_null	a,b	a	5	const	4	Using where
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| explain select * from t1 where (a is null and b>a) or a is null and b=7 limit 2;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	ref	a,b	a	5	const	3	Using where
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| explain select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	ref	a,b	a	5	const	3	Using where
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| explain select * from t1 where a > 1 and a < 3 limit 1;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	range	a	a	5	NULL	1	Using where
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| explain select * from t1 where a is null and b=7 or a > 1 and a < 3 limit 1;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	range	a,b	a	5	NULL	4	Using where
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| explain select * from t1 where a > 8 and a < 9;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	range	a	a	5	NULL	1	Using where
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| explain select * from t1 where b like "6%";
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	range	b	b	12	NULL	1	Using where
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| select * from t1 where a is null;
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| a	b	c
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| NULL	7	0
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| NULL	9	0
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| NULL	9	0
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| select * from t1 where a is null and b = 7 and c=0;
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| a	b	c
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| NULL	7	0
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| select * from t1 where a<=>b limit 2;
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| a	b	c
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| 1	1	0
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| 2	2	0
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| select * from t1 where (a is null or a > 0 and a < 3) and b < 5 limit 3;
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| a	b	c
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| 1	1	0
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| 2	2	0
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| select * from t1 where (a is null or a > 0 and a < 3) and b > 7 limit 3;
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| a	b	c
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| NULL	9	0
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| NULL	9	0
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| select * from t1 where (a is null or a = 7) and b=7 and c=0;
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| a	b	c
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| 7	7	0
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| NULL	7	0
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| select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
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| a	b	c
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| NULL	7	0
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| NULL	9	0
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| NULL	9	0
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| select * from t1 where b like "6%";
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| a	b	c
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| 6	6	0
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| drop table t1;
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| rename table t2 to t1;
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| alter table t1 modify b int null;
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| insert into t1 values (7,null), (8,null), (8,7);
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| explain select * from t1 where a = 7 and (b=7 or b is null);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	ref_or_null	a,b	a	10	const,const	2	Using where; Using index
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| select * from t1 where a = 7 and (b=7 or b is null);
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| a	b
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| 7	7
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| 7	NULL
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| explain select * from t1 where (a = 7 or a is null) and (b=7 or b is null);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	ref_or_null	a,b	a	5	const	4	Using where; Using index
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| select * from t1 where (a = 7 or a is null) and (b=7 or b is null);
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| a	b
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| 7	NULL
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| 7	7
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| NULL	7
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| explain select * from t1 where (a = 7 or a is null) and (a = 7 or a is null);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	ref_or_null	a	a	5	const	5	Using where; Using index
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| select * from t1 where (a = 7 or a is null) and (a = 7 or a is null);
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| a	b
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| 7	NULL
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| 7	7
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| NULL	7
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| NULL	9
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| NULL	9
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| create table t2 (a int);
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| insert into t2 values (7),(8);
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| explain select * from t2 straight_join t1 where t1.a=t2.a and b is null;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	2	
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| 1	SIMPLE	t1	ref	a,b	a	10	test.t2.a,const	2	Using where; Using index
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| drop index b on t1;
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| explain select * from t2,t1 where t1.a=t2.a and b is null;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	2	
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| 1	SIMPLE	t1	ref	a	a	10	test.t2.a,const	2	Using where; Using index
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| select * from t2,t1 where t1.a=t2.a and b is null;
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| a	a	b
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| 7	7	NULL
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| 8	8	NULL
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| explain select * from t2,t1 where t1.a=t2.a and (b= 7 or b is null);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	2	
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| 1	SIMPLE	t1	ref_or_null	a	a	10	test.t2.a,const	4	Using where; Using index
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| select * from t2,t1 where t1.a=t2.a and (b= 7 or b is null);
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| a	a	b
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| 7	7	7
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| 7	7	NULL
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| 8	8	7
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| 8	8	NULL
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| explain select * from t2,t1 where (t1.a=t2.a or t1.a is null) and b= 7;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	2	
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| 1	SIMPLE	t1	ref_or_null	a	a	10	test.t2.a,const	4	Using where; Using index
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| select * from t2,t1 where (t1.a=t2.a or t1.a is null) and b= 7;
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| a	a	b
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| 7	7	7
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| 7	NULL	7
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| 8	8	7
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| 8	NULL	7
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| explain select * from t2,t1 where (t1.a=t2.a or t1.a is null) and (b= 7 or b is null);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	2	
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| 1	SIMPLE	t1	ref_or_null	a	a	5	test.t2.a	4	Using where; Using index
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| select * from t2,t1 where (t1.a=t2.a or t1.a is null) and (b= 7 or b is null);
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| a	a	b
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| 7	7	NULL
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| 7	7	7
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| 7	NULL	7
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| 8	8	NULL
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| 8	8	7
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| 8	NULL	7
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| insert into t2 values (null),(6);
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| delete from t1 where a=8;
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| explain select * from t2,t1 where t1.a=t2.a or t1.a is null;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	4	
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| 1	SIMPLE	t1	ref_or_null	a	a	5	test.t2.a	4	Using where; Using index
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| explain select * from t2,t1 where t1.a<=>t2.a or (t1.a is null and t1.b <> 9);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	4	
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| 1	SIMPLE	t1	ref_or_null	a	a	5	test.t2.a	4	Using where; Using index
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| select * from t2,t1 where t1.a<=>t2.a or (t1.a is null and t1.b <> 9);
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| a	a	b
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| 7	7	NULL
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| 7	7	7
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| 7	NULL	7
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| 8	NULL	7
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| NULL	NULL	7
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| NULL	NULL	9
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| NULL	NULL	9
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| 6	6	6
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| 6	NULL	7
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| drop table t1,t2;
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| CREATE TABLE t1 (
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| id int(10) unsigned NOT NULL auto_increment,
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| uniq_id int(10) unsigned default NULL,
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| PRIMARY KEY  (id),
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| UNIQUE KEY idx1 (uniq_id)
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| ) ENGINE=MyISAM;
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| CREATE TABLE t2 (
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| id int(10) unsigned NOT NULL auto_increment,
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| uniq_id int(10) unsigned default NULL,
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| PRIMARY KEY  (id)
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| ) ENGINE=MyISAM;
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| INSERT INTO t1 VALUES (1,NULL),(2,NULL),(3,1),(4,2),(5,NULL),(6,NULL),(7,3),(8,4),(9,NULL),(10,NULL);
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| INSERT INTO t2 VALUES (1,NULL),(2,NULL),(3,1),(4,2),(5,NULL),(6,NULL),(7,3),(8,4),(9,NULL),(10,NULL);
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| explain select id from t1 where uniq_id is null;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	ref	idx1	idx1	5	const	1	Using where
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| explain select id from t1 where uniq_id =1;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t1	const	idx1	idx1	5	const	1	
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| UPDATE t1 SET id=id+100 where uniq_id is null;
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| UPDATE t2 SET id=id+100 where uniq_id is null;
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| select id from t1 where uniq_id is null;
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| id
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| 101
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| 102
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| 105
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| 106
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| 109
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| 110
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| select id from t2 where uniq_id is null;
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| id
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| 101
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| 102
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| 105
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| 106
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| 109
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| 110
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| DELETE FROM t1 WHERE uniq_id IS NULL;
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| DELETE FROM t2 WHERE uniq_id IS NULL;
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| SELECT * FROM t1 ORDER BY uniq_id, id;
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| id	uniq_id
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| 3	1
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| 4	2
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| 7	3
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| 8	4
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| SELECT * FROM t2 ORDER BY uniq_id, id;
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| id	uniq_id
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| 3	1
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| 4	2
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| 7	3
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| 8	4
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| DROP table t1,t2;
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| CREATE TABLE `t1` (
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| `order_id` char(32) NOT NULL default '',
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| `product_id` char(32) NOT NULL default '',
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| `product_type` int(11) NOT NULL default '0',
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| PRIMARY KEY  (`order_id`,`product_id`,`product_type`)
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| ) ENGINE=MyISAM;
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| CREATE TABLE `t2` (
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| `order_id` char(32) NOT NULL default '',
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| `product_id` char(32) NOT NULL default '',
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| `product_type` int(11) NOT NULL default '0',
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| PRIMARY KEY  (`order_id`,`product_id`,`product_type`)
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| ) ENGINE=MyISAM;
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| INSERT INTO t1 (order_id, product_id, product_type) VALUES
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| ('3d7ce39b5d4b3e3d22aaafe9b633de51',1206029, 3),
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| ('3d7ce39b5d4b3e3d22aaafe9b633de51',5880836, 3),
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| ('9d9aad7764b5b2c53004348ef8d34500',2315652, 3);
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| INSERT INTO t2 (order_id, product_id, product_type) VALUES
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| ('9d9aad7764b5b2c53004348ef8d34500',2315652, 3);
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| select t1.* from t1
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| left join t2 using(order_id, product_id, product_type)
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| where t2.order_id=NULL;
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| order_id	product_id	product_type
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| select t1.* from t1
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| left join t2 using(order_id, product_id, product_type)
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| where t2.order_id is NULL;
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| order_id	product_id	product_type
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| 3d7ce39b5d4b3e3d22aaafe9b633de51	1206029	3
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| 3d7ce39b5d4b3e3d22aaafe9b633de51	5880836	3
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| drop table t1,t2;
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| create table t1 (id int);
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| insert into t1 values (null), (0);
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| create table t2 (id int);
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| insert into t2 values (null);
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| select * from t1, t2 where t1.id = t2.id;
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| id	id
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| alter table t1 add key id (id);
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| select * from t1, t2 where t1.id = t2.id;
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| id	id
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| drop table t1,t2;
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| create table t1 (
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| id  integer,
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| id2 integer not null,
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| index (id),
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| index (id2)
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| );
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| insert into t1 values(null,null),(1,1);
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| Warnings:
 | |
| Warning	1048	Column 'id2' cannot be null
 | |
| select * from t1;
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| id	id2
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| NULL	0
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| 1	1
 | |
| select * from t1 where id <=> null;
 | |
| id	id2
 | |
| NULL	0
 | |
| select * from t1 where id <=> null or id > 0;
 | |
| id	id2
 | |
| NULL	0
 | |
| 1	1
 | |
| select * from t1 where id is null or id > 0;
 | |
| id	id2
 | |
| NULL	0
 | |
| 1	1
 | |
| select * from t1 where id2 <=> null or id2 > 0;
 | |
| id	id2
 | |
| 1	1
 | |
| select * from t1 where id2 is null or id2 > 0;
 | |
| id	id2
 | |
| 1	1
 | |
| delete from t1 where id <=> NULL;
 | |
| select * from t1;
 | |
| id	id2
 | |
| 1	1
 | |
| drop table t1;
 | |
| CREATE TABLE t1 (a int);
 | |
| CREATE TABLE t2 (a int, b int, INDEX idx(a));
 | |
| CREATE TABLE t3 (b int, INDEX idx(b));
 | |
| CREATE TABLE t4 (b int, INDEX idx(b));
 | |
| INSERT INTO t1 VALUES (1), (2), (3), (4);
 | |
| INSERT INTO t2 VALUES (1, 1), (3, 1);
 | |
| INSERT INTO t3 VALUES 
 | |
| (NULL), (NULL), (NULL), (NULL), (NULL),
 | |
| (NULL), (NULL), (NULL), (NULL), (NULL);
 | |
| INSERT INTO t4 SELECT * FROM t3;
 | |
| INSERT INTO t3 SELECT * FROM t4;
 | |
| INSERT INTO t4 SELECT * FROM t3;
 | |
| INSERT INTO t3 SELECT * FROM t4;
 | |
| INSERT INTO t4 SELECT * FROM t3;
 | |
| INSERT INTO t3 SELECT * FROM t4;
 | |
| INSERT INTO t4 SELECT * FROM t3;
 | |
| INSERT INTO t3 SELECT * FROM t4;
 | |
| INSERT INTO t4 SELECT * FROM t3;
 | |
| INSERT INTO t3 SELECT * FROM t4;
 | |
| INSERT INTO t4 SELECT * FROM t3;
 | |
| INSERT INTO t3 SELECT * FROM t4;
 | |
| INSERT INTO t4 SELECT * FROM t3;
 | |
| INSERT INTO t3 SELECT * FROM t4;
 | |
| INSERT INTO t4 SELECT * FROM t3;
 | |
| INSERT INTO t3 SELECT * FROM t4;
 | |
| INSERT INTO t3 VALUES (2), (3);
 | |
| ANALYZE table t1, t2, t3;
 | |
| Table	Op	Msg_type	Msg_text
 | |
| test.t1	analyze	status	OK
 | |
| test.t2	analyze	status	OK
 | |
| test.t3	analyze	status	OK
 | |
| SELECT COUNT(*) FROM t3;
 | |
| COUNT(*)
 | |
| 15972
 | |
| EXPLAIN SELECT SQL_CALC_FOUND_ROWS * FROM t1 LEFT JOIN t2 ON t1.a=t2.a
 | |
| LEFT JOIN t3 ON t2.b=t3.b;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	4	
 | |
| 1	SIMPLE	t2	ref	idx	idx	5	test.t1.a	1	
 | |
| 1	SIMPLE	t3	ref	idx	idx	5	test.t2.b	1	Using index
 | |
| FLUSH STATUS ;
 | |
| SELECT SQL_CALC_FOUND_ROWS * FROM t1 LEFT JOIN t2 ON t1.a=t2.a
 | |
| LEFT JOIN t3 ON t2.b=t3.b;
 | |
| a	a	b	b
 | |
| 1	1	1	NULL
 | |
| 2	NULL	NULL	NULL
 | |
| 3	3	1	NULL
 | |
| 4	NULL	NULL	NULL
 | |
| SELECT FOUND_ROWS();
 | |
| FOUND_ROWS()
 | |
| 4
 | |
| SHOW STATUS LIKE "handler_read%";
 | |
| Variable_name	Value
 | |
| Handler_read_first	0
 | |
| Handler_read_key	6
 | |
| Handler_read_next	2
 | |
| Handler_read_prev	0
 | |
| Handler_read_rnd	0
 | |
| Handler_read_rnd_next	5
 | |
| DROP TABLE t1,t2,t3,t4;
 |