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	75d354a23a
	
	
	
		
			
			Gain MySQL compatibility by allowing table aliases in a single table statement. This now supports the syntax of: DELETE [delete_opts] FROM tbl_name [[AS] tbl_alias] [PARTITION (partition_name [, partition_name] ...)] .... The delete.test is from MySQL commit 1a72b69778a9791be44525501960b08856833b8d / Change-Id: Iac3a2b5ed993f65b7f91acdfd60013c2344db5c0. Co-Author: Gleb Shchepa <gleb.shchepa@oracle.com> (for delete.test) Reviewed by Igor Babaev (igor@mariadb.com)
		
			
				
	
	
		
			407 lines
		
	
	
	
		
			11 KiB
		
	
	
	
		
			Text
		
	
	
	
	
	
			
		
		
	
	
			407 lines
		
	
	
	
		
			11 KiB
		
	
	
	
		
			Text
		
	
	
	
	
	
| create table t1(c1 integer not null,c2 integer not null, key (c1))
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| ENGINE=InnoDB STATS_PERSISTENT=1;
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| create view v1 as select * from t1 where c1 in (0,1);
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| insert t1 select 0,seq from seq_1_to_500;
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| insert t1 select 1,seq from seq_1_to_100;
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| insert t1 select 2,seq from seq_1_to_50;
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| insert t1 select 3,seq from seq_1_to_20;
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| analyze table t1;
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| Table	Op	Msg_type	Msg_text
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| test.t1	analyze	status	Engine-independent statistics collected
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| test.t1	analyze	status	OK
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| #
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| # Delete with limit (quick select - range acces)
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| #
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| start transaction;
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| delete from t1 where (select count(*) from t1 b where b.c1=t1.c1) = 500 limit 1;
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| affected rows: 1
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| delete from t1 where (select count(*) from t1 b where b.c1=t1.c1) = 500 limit 1;
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| affected rows: 0
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| select count(*) from v1 where c1=0;
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| count(*)
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| 499
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| rollback;
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| #
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| # Delete
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| #
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| start transaction;
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| delete from t1 where (select count(*) from t1 b where b.c1=t1.c1) = 500 ;
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| affected rows: 500
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| rollback;
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| #
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| # Delete with exists
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| #
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| start transaction;
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| select count(*) from v1 where c1=2;
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| count(*)
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| 0
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| delete from t1 where c1=2 and exists(select 'x' from t1 b where b.c2<10);
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| affected rows: 50
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| delete from t1 where c1=2 and exists(select 'x' from t1 b where b.c2<10);
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| affected rows: 0
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| select count(*) from v1 where c1=2;
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| count(*)
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| 0
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| rollback;
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| #
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| # Delete through a view with limit (range access)
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| #
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| start transaction;
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| explain delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 limit 1;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	PRIMARY	t1	range	c1	c1	4	NULL	600	Using index condition; Using where
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| 2	DEPENDENT SUBQUERY	b	ref	c1	c1	4	test.t1.c1	167	Using index
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| delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 limit 1;
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| affected rows: 1
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| delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 limit 1;
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| affected rows: 0
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| select count(*) from v1 where c1=0;
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| count(*)
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| 499
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| rollback;
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| #
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| # Delete through a view (ALL access)
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| #
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| start transaction;
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| explain delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	PRIMARY	t1	range	c1	c1	4	NULL	#	Using index condition; Using where
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| 2	DEPENDENT SUBQUERY	b	ref	c1	c1	4	test.t1.c1	#	Using index
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| delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 ;
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| affected rows: 500
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| select count(*) from v1 where c1=0;
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| count(*)
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| 0
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| rollback;
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| #
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| # Delete failed due to trigger
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| #
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| create trigger trg after delete on t1 for each row
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| begin
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| declare c int;
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| begin
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| if old.c1 = 1 then
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| select count(*) into c from t1 where c1!=old.c1;
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| SIGNAL SQLSTATE '45000' set table_name=c;
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| end if;
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| end;
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| end;
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| /
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| start transaction;
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| delete from t1 where c1=1 and (select count(*) from t1 b where b.c1=t1.c1) > 0 order by c2 asc limit 10;
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| ERROR 45000: Unhandled user-defined exception condition
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| rollback;
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| start transaction;
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| delete from t1 where (select count(*) from t1 b where b.c1=t1.c1) > 0 order by c1 desc limit 100;
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| ERROR 45000: Unhandled user-defined exception condition
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| select c1,count(*) from t1 group by c1;
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| c1	count(*)
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| 0	500
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| 1	100
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| 2	50
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| 3	20
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| rollback;
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| drop trigger trg;
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| #
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| # Delete through a view with returning
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| #
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| start transaction;
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| delete from t1 where (select count(*) from t1 b where b.c1=t1.c1) = 500 order by c2 asc limit 10 returning c1,c2;
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| c1	c2
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| 0	1
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| 0	2
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| 0	3
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| 0	4
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| 0	5
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| 0	6
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| 0	7
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| 0	8
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| 0	9
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| 0	10
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| rollback;
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| start transaction;
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| delete from t1 where (select count(*) from t1 b where b.c1=t1.c1) = 500 order by c2 desc limit 10 returning c1,c2;
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| c1	c2
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| 0	491
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| 0	492
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| 0	493
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| 0	494
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| 0	495
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| 0	496
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| 0	497
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| 0	498
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| 0	499
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| 0	500
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| rollback;
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| drop view v1;
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| drop table t1;
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| #
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| # Delete from table with more than 150000 rows
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| #
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| create table t1(c1 integer not null,c2 integer not null, key (c1));
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| insert t1 select 0,seq from seq_1_to_128000;
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| insert t1 select 1,seq from seq_1_to_25600;
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| select count(*) from t1;
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| count(*)
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| 153600
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| # with a lot of memory for sort_buffer_size
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| set session sort_buffer_size = 1024000;
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| delete from t1 where c1=0 and exists(select 'x' from t1 b where b.c1<10);
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| affected rows: 128000
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| # with little memory for sort_buffer_size
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| insert t1 select 0,seq from seq_1_to_128000;
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| set session sort_buffer_size = 1024;
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| delete from t1 where c1=0 and exists(select 'x' from t1 b where b.c1<10);
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| affected rows: 128000
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| drop table t1;
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| #
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| # MDEV-17954: multi-table DELETE with the same source and target
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| #
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| create table t1 (c1 int, c2 int, c3 int);
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| insert into t1 values
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| (1,1,1), (1,2,2), (1,3,3), (2,1,4), (2,2,5), (2,3,6), (2,4,7), (2,5,8);
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| #
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| # Single-table DELETE with the same source and target
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| # handled as multi-table DELETE
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| #
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| explain delete from t1
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| where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1 and a.c2 < 3);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	8	Using where
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| 1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	8	Using where; FirstMatch(t1)
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| delete from t1
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| where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1 and a.c2 < 3);
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| select * from t1;
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| c1	c2	c3
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| 1	3	3
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| 2	3	6
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| 2	4	7
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| 2	5	8
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| delete from t1;
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| insert into t1 values
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| (1,1,1), (1,2,2), (1,3,3), (2,1,4), (2,2,5), (2,3,6), (2,4,7), (2,5,8);
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| prepare stmt from "delete from t1
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| where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1 and a.c2 < 3)";
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| execute stmt;
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| select * from t1;
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| c1	c2	c3
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| 1	3	3
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| 2	3	6
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| 2	4	7
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| 2	5	8
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| delete from t1;
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| insert into t1 values
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| (2,2,5), (2,3,6), (2,4,7), (2,5,8);
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| execute stmt;
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| select * from t1;
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| c1	c2	c3
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| 2	3	6
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| 2	4	7
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| 2	5	8
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| deallocate prepare stmt;
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| delete from t1;
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| insert into t1 values
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| (1,1,1), (1,2,2), (1,3,3), (2,1,4), (2,2,5), (2,3,6), (2,4,7), (2,5,8);
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| #
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| # Multi-table DELETE with the same source and target
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| #
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| create table t2 (c1 int, c2 int, c3 int);
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| insert into t2 values
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| (1,1,1), (1,2,2), (1,3,3), (2,1,4), (2,2,5), (2,3,6), (2,5,8);
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| explain delete from t1 using t1,t2
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| where t1.c2 = t2.c2 and t1.c1 > 1;
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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	7	
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| 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	8	Using where
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| delete from t1 using t1,t2
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| where t1.c2 = t2.c2 and t1.c1 > 1;
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| select * from t1;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| 1	3	3
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| 2	4	7
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| delete from t1;
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| insert into t1 values
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| (1,1,1), (1,2,2), (1,3,3), (2,1,4), (2,2,5), (2,3,6), (2,4,7), (2,5,8);
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| prepare stmt from "delete from t1 using t1,t2
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| where t1.c2 = t2.c2 and t1.c1 > 1";
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| execute stmt;
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| select * from t1;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| 1	3	3
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| 2	4	7
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| delete from t1;
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| insert into t1 values
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| (2,2,5), (2,3,6), (2,4,7), (2,5,8);
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| execute stmt;
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| select * from t1;
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| c1	c2	c3
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| 2	4	7
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| deallocate prepare stmt;
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| explain delete from t1 using t1,t2
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| where t1.c2 = t2.c2 and t1.c1 > 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	system	NULL	NULL	NULL	NULL	1	
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| 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	7	Using where
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| delete from t1 using t1,t2
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| where t1.c2 = t2.c2 and t1.c1 > 1;
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| select * from t1;
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| c1	c2	c3
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| 2	4	7
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| delete from t1;
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| insert into t1 values
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| (1,1,1), (1,2,2), (1,3,3), (2,1,4), (2,2,5), (2,3,6), (2,4,7), (2,5,8);
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| prepare stmt from "delete from t1 using t1,t2
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| where t1.c2 = t2.c2 and t1.c1 > 1";
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| execute stmt;
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| select * from t1;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| 1	3	3
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| 2	4	7
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| delete from t1;
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| insert into t1 values
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| (2,2,5), (2,3,6), (2,4,7), (2,5,8);
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| execute stmt;
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| select * from t1;
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| c1	c2	c3
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| 2	4	7
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| deallocate prepare stmt;
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| delete from t1;
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| insert into t1 values
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| (1,1,1), (1,2,2), (1,3,3), (2,1,4), (2,2,5), (2,3,6), (2,4,7), (2,5,8);
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| explain delete from t1,t2 using t1,t2
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| where t1.c2 = t2.c2 and t1.c1 > 1 and t2.c1 > 1;
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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	7	Using where
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| 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	8	Using where
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| delete from t1,t2 using t1,t2
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| where t1.c2 = t2.c2 and t1.c1 > 1 and t2.c1 > 1;
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| select * from t1;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| 1	3	3
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| 2	4	7
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| select * from t2;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| 1	3	3
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| delete from t1;
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| insert into t1 values
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| (1,1,1), (1,2,2), (1,3,3), (2,1,4), (2,2,5), (2,3,6), (2,4,7), (2,5,8);
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| delete from t2;
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| insert into t2 values
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| (1,1,1), (1,2,2), (1,3,3), (2,1,4), (2,2,5), (2,3,6), (2,5,8);
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| prepare stmt from "delete from t1,t2 using t1,t2
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| where t1.c2 = t2.c2 and t1.c1 > 1 and t2.c1 > 1";
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| execute stmt;
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| select * from t1;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| 1	3	3
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| 2	4	7
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| select * from t2;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| 1	3	3
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| delete from t1;
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| insert into t1 values
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| (1,2,2), (1,3,3), (2,2,5), (2,3,6), (2,4,7), (2,5,8);
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| delete from t2;
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| insert into t2 values
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| (1,1,1), (1,2,2), (1,3,3), (2,1,4), (2,2,5);
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| execute stmt;
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| select * from t1;
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| c1	c2	c3
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| 1	2	2
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| 1	3	3
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| 2	3	6
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| 2	4	7
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| 2	5	8
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| select * from t2;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| 1	3	3
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| 2	1	4
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| deallocate prepare stmt;
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| drop table t1,t2;
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| # End of 11.1
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| #
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| # MDEV-33988 DELETE (single table) to support table aliases
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| #
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| create table t1 (c1 int, c2 int, c3 int);
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| insert into t1 values
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| (1,1,1), (1,2,2), (1,3,3), (2,1,4), (2,2,5), (2,3,6), (2,5,7), (3,5,8);
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| create table t2 (id int auto_increment primary key, a int, key(a));
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| insert into t2(a) values (3), (5), (-1);
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| # 1. The alias in delete coincides with the table name in IN subquery.
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| explain extended
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| delete from t1 t2 where t2.c1 in (select a from t2);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
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| 1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	8	100.00	Using where
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| 1	PRIMARY	t2	ref	a	a	5	test.t2.c1	1	100.00	Using index; FirstMatch(t2)
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| Warnings:
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| Note	1003	delete  from `test`.`t1` `t2` using (`test`.`t2`) where `test`.`t2`.`a` = `test`.`t2`.`c1`
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| delete from t1 t2 where t2.c1 in (select a from t2);
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| select * from t1;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| 1	3	3
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| 2	1	4
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| 2	2	5
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| 2	3	6
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| 2	5	7
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| # 2. The alias in delete is different from the alias in IN subquery
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| explain extended
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| delete from t1 t_x where t_x.c2 IN (select a from t2 as t_y);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
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| 1	PRIMARY	t_x	ALL	NULL	NULL	NULL	NULL	7	100.00	Using where
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| 1	PRIMARY	t_y	ref	a	a	5	test.t_x.c2	1	100.00	Using index; FirstMatch(t_x)
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| Warnings:
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| Note	1003	delete  from `test`.`t1` `t_x` using (`test`.`t2` `t_y`) where `test`.`t_y`.`a` = `test`.`t_x`.`c2`
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| delete from t1 t_x where t_x.c2 IN (select a from t2 as t_y);
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| select * from t1;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| 2	1	4
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| 2	2	5
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| # 3. The alias in delete is the same as the alias in IN subquery.
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| explain extended
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| delete from t1 as t_x where t_x.c3 IN (select a from t2 t_x);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
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| 1	PRIMARY	t_x	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
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| 1	PRIMARY	t_x	ref	a	a	5	test.t_x.c3	1	100.00	Using index; FirstMatch(t_x)
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| Warnings:
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| Note	1003	delete  from `test`.`t1` `t_x` using (`test`.`t2` `t_x`) where `test`.`t_x`.`a` = `test`.`t_x`.`c3`
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| delete from t1 as t_x where t_x.c3 IN (select a from t2 t_x);
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| select * from t1;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| 2	1	4
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| # 4. The table in delete is the alias in IN subquery
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| explain extended
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| delete from t1 t2 where t2.c1 IN (select a -1  from t2 as t1);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
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| 1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	3	100.00	
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| 1	PRIMARY	t1	index	NULL	a	5	NULL	3	33.33	Using where; Using index; FirstMatch(t2)
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| Warnings:
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| Note	1003	delete  from `test`.`t1` `t2` using (`test`.`t2` `t1`) where `test`.`t2`.`c1` = `test`.`t1`.`a` - 1
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| delete from t1 t2 where t2.c1 IN (select a -1  from t2 as t1);
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| select * from t1;
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| c1	c2	c3
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| 1	1	1
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| 1	2	2
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| drop table t1, t2;
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| # End of 11.6
 |