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156 lines
4.1 KiB
Text
156 lines
4.1 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 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 ALL c1 NULL NULL NULL # 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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