SET @save_timeout = @@GLOBAL.innodb_lock_wait_timeout; SET GLOBAL innodb_lock_wait_timeout = 1; SET @save_isolation = @@GLOBAL.transaction_isolation; SET GLOBAL TRANSACTION ISOLATION LEVEL READ COMMITTED;
drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9,t10;
create table t1 (id int not null, f_id int not null, f int not null,
primary key(f_id, id)) engine = InnoDB;
create table t2 (id int not null,s_id int not null,s varchar(200),
primary key(id)) engine = InnoDB;
INSERT INTO t1 VALUES (8, 1, 3);
INSERT INTO t1 VALUES (1, 2, 1);
INSERT INTO t2 VALUES (1, 0, '');
INSERT INTO t2 VALUES (8, 1, '');
commit;
DELETE ml.* FROM t1 AS ml LEFT JOIN t2 AS mm ON (mm.id=ml.id)
WHERE mm.id IS NULL;
select ml.* from t1 as ml left join t2 as mm on (mm.id=ml.id)
where mm.id is null lock in share mode;
id f_id f
drop table t1,t2;
connect a,localhost,root,,;
connect b,localhost,root,,;
connection a;
create table t1(a int not null, b int, primary key(a)) engine = InnoDB;
insert into t1 values(1,1),(2,2),(3,1),(4,2),(5,1),(6,2),(7,3);
commit; set autocommit = 0;
select * from t1 lock in share mode;
a b 11 22 31 42 51 62 73
update t1 set b = 5 where b = 1;
connection b; set autocommit = 0;
select * from t1 where a = 2and b = 2 for update; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection a;
commit;
connection b;
commit;
drop table t1;
connection default;
disconnect a;
disconnect b;
connect a,localhost,root,,;
connect b,localhost,root,,;
connection a;
create table t1(a int not null, b int, primary key(a)) engine = InnoDB;
insert into t1 values(1,1),(2,2),(3,1),(4,2),(5,1),(6,2),(7,3);
commit; set autocommit = 0;
update t1 set b = 5 where b = 1;
connection b; set autocommit = 0;
select * from t1 where a = 7and b = 3 for update;
a b 73
commit;
connection a;
commit;
drop table t1;
connection default;
disconnect a;
disconnect b;
connect a,localhost,root,,;
connect b,localhost,root,,;
connection a;
create table t1(a int not null, b int, primary key(a)) engine = InnoDB;
insert into t1 values (1,2),(5,3),(4,2);
create table t2(d int not null, e int, primary key(d)) engine = InnoDB;
insert into t2 values (8,6),(12,1),(3,1);
commit; set autocommit = 0;
select * from t2 for update;
d e 31 86 121
connection b; set autocommit = 0;
insert into t1 select * from t2;
update t1 set b = (select e from t2 where a = d);
create table t3(d int not null, e int, primary key(d)) engine = InnoDB
select * from t2;
commit;
connection a;
commit;
connection default;
disconnect a;
disconnect b;
drop table t1, t2, t3;
connect a,localhost,root,,;
connect b,localhost,root,,;
connect c,localhost,root,,;
connect d,localhost,root,,; SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
connect e,localhost,root,,;
connect f,localhost,root,,;
connect g,localhost,root,,; SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
connect h,localhost,root,,;
connect i,localhost,root,,;
connect j,localhost,root,,; SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
connection a;
create table t1(a int not null, b int, primary key(a)) engine = InnoDB;
insert into t1 values (1,2),(5,3),(4,2);
create table t2(a int not null, b int, primary key(a)) engine = InnoDB;
insert into t2 values (8,6),(12,1),(3,1);
create table t3(d int not null, b int, primary key(d)) engine = InnoDB;
insert into t3 values (8,6),(12,1),(3,1);
create table t5(a int not null, b int, primary key(a)) engine = InnoDB;
insert into t5 values (1,2),(5,3),(4,2);
create table t6(d int not null, e int, primary key(d)) engine = InnoDB;
insert into t6 values (8,6),(12,1),(3,1);
create table t8(a int not null, b int, primary key(a)) engine = InnoDB;
insert into t8 values (1,2),(5,3),(4,2);
create table t9(d int not null, e int, primary key(d)) engine = InnoDB;
insert into t9 values (8,6),(12,1),(3,1);
commit; set autocommit = 0;
select * from t2 for update;
a b 31 86 121
connection b; set autocommit = 0; SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE;
insert into t1 select * from t2;
connection c; set autocommit = 0; SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE;
update t3 set b = (select b from t2 where a = d);
connection d; set autocommit = 0; SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE;
create table t4(a int not null, b int, primary key(a)) select * from t2;
connection e; set autocommit = 0;
insert into t5 (select * from t2 lock in share mode);
connection f; set autocommit = 0;
update t6 set e = (select b from t2 where a = d lock in share mode);
connection g; set autocommit = 0;
create table t7(a int not null, b int, primary key(a)) select * from t2 lock in share mode;
connection h; set autocommit = 0;
insert into t8 (select * from t2 for update);
connection i; set autocommit = 0;
update t9 set e = (select b from t2 where a = d for update);
connection j; set autocommit = 0;
create table t10(a int not null, b int, primary key(a)) select * from t2 for update;
connection b; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection c; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection d; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection e; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection f; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection g; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection h; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection i; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection j; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection a;
commit;
connection default;
disconnect a;
disconnect b;
disconnect c;
disconnect d;
disconnect e;
disconnect f;
disconnect g;
disconnect h;
disconnect i;
disconnect j;
drop table t1, t2, t3, t5, t6, t8, t9; SET GLOBAL innodb_lock_wait_timeout = @save_timeout; SET GLOBAL transaction_isolation = @save_isolation;
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.11 Sekunden
(vorverarbeitet am 2026-10-08)
¤
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