mysql read committed

read commit;

Oracle采用的也是 read committed

默认是:

mysql> SELECT @@GLOBAL.tx_isolation, @@tx_isolation;

+———————–+—————–+

| @@GLOBAL.tx_isolation | @@tx_isolation |

+———————–+—————–+

| REPEATABLE-READ | REPEATABLE-READ |

+———————–+—————–+

1 row in set (0.00 sec)

set session transaction isolation level read committed;

mysql> SELECT @@GLOBAL.tx_isolation, @@tx_isolation;

+———————–+—————-+

| @@GLOBAL.tx_isolation | @@tx_isolation |

+———————–+—————-+

| REPEATABLE-READ | READ-COMMITTED |

+———————–+—————-+

1 row in set (0.00 sec)

SESSION A:

set autocommit=0;

set session transaction isolation level read committed;

SESSION B:

set autocommit=0;

set session transaction isolation level read committed;

SESSION B:

mysql> insert into t1 values(200);

Query OK, 1 row affected (0.00 sec)

mysql> select * from t1;

+——+

| id |

+——+

| 100 |

| 200 |

+——+

2 rows in set (0.00 sec)

mysql> commit;

Query OK, 0 rows affected (0.00 sec)

SESSION A:

mysql> select * from t1;

+——+

| id |

+——+

| 100 |

| 200 |

+——+

2 rows in set (0.00 sec

只要B提交,A就能看到