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具有两个sql insert的事务

lastinsertid transactions spring mysql java

Alberto Zaccagni · 技术社区 · 15 年前

我有两个sql insert要做(例如表A和B中的示例),它们在事务中,因为我希望数据库保持一致,也就是说,A中的元组必须在B中有引用。

在第二个insert中,我需要来自第一个insert的id,但是在对事务进行提交之前,我不会得到这个id。
所以我被困住了。我不想从事务中删除第一个insert,可能第一个insert正常,而第二个则不正常,这使我在数据库中的状态不一致。

在这种情况下,最佳做法是什么?

编辑:代码如下:

TransactionStatus txStatus = transactionManager.getTransaction(txDefinition);
try{
    Integer aId = insertIntoA();
    insertIntoB(aId);
}catch(){
    transactionManager.rollback(txStatus);
    throw new CustomException(); 
}
transactionManager.commit(txStatus);

我想指出的是我不明白

3 回复 | 直到 15 年前

T.J. Crowder 15 年前

在MySQL上,在 insertIntoA 你应该能够做到:

SELECT LAST_INSERT_ID()

identity 要查找的列值。

编辑

mysql> create table A (id int(11) not null auto_increment, descr varchar(64), primary key (id));
Query OK, 0 rows affected (0.13 sec)

mysql> create table B (fk int(11) not null, descr varchar(64));
Query OK, 0 rows affected (0.06 sec)

mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)

mysql> insert into A (descr) values ('Testing 1 2 3');
Query OK, 1 row affected (0.00 sec)

mysql> select last_insert_id();
+------------------+
| last_insert_id() |
+------------------+
|                1 |
+------------------+
1 row in set (0.03 sec)

mysql> insert into B (fk, descr) values (1, 'Test complete');
Query OK, 1 row affected (0.00 sec)

mysql> commit;
Query OK, 0 rows affected (0.03 sec)

mysql> select * from A;
+----+---------------+
| id | descr         |
+----+---------------+
|  1 | Testing 1 2 3 |
+----+---------------+
1 row in set (0.02 sec)

mysql> select * from B;
+----+---------------+
| fk | descr         |
+----+---------------+
|  1 | Test complete |
+----+---------------+
1 row in set (0.00 sec)

mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)

mysql> insert into A (descr) values ('Second test');
Query OK, 1 row affected (0.01 sec)

mysql> select last_insert_id();
+------------------+
| last_insert_id() |
+------------------+
|                2 |
+------------------+
1 row in set (0.00 sec)

mysql> insert into B (fk, descr) values (2, 'Second test complete');
Query OK, 1 row affected (0.00 sec)

mysql> commit;
Query OK, 0 rows affected (0.08 sec)

mysql> select * from A;
+----+---------------+
| id | descr         |
+----+---------------+
|  1 | Testing 1 2 3 |
|  2 | Second test   |
+----+---------------+
2 rows in set (0.02 sec)

mysql> select * from B;
+----+----------------------+
| fk | descr                |
+----+----------------------+
|  1 | Test complete        |
|  2 | Second test complete |
+----+----------------------+
2 rows in set (0.00 sec)

mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)

mysql> insert into A (descr) values ('We''ll roll this one back.');
Query OK, 1 row affected (0.00 sec)

mysql> select last_insert_id();
+------------------+
| last_insert_id() |
+------------------+
|                3 |
+------------------+
1 row in set (0.00 sec)

mysql> insert into B (fk, descr) values (3, 'Won''t see this one.');
Query OK, 1 row affected (0.00 sec)

mysql> select * from B;
+----+----------------------+
| fk | descr                |
+----+----------------------+
|  1 | Test complete        |
|  2 | Second test complete |
|  3 | Won't see this one.  |
+----+----------------------+
3 rows in set (0.00 sec)

mysql> rollback;
Query OK, 0 rows affected (0.03 sec)

mysql> select * from A;
+----+---------------+
| id | descr         |
+----+---------------+
|  1 | Testing 1 2 3 |
|  2 | Second test   |
+----+---------------+
2 rows in set (0.00 sec)

mysql> select * from B;
+----+----------------------+
| fk | descr                |
+----+----------------------+
|  1 | Test complete        |
|  2 | Second test complete |
+----+----------------------+
2 rows in set (0.00 sec)

Brian Agnew 15 年前

你在看什么证件?您应该能够获得(比如)通过序列自动生成的主键ID(一个常见的场景) 不管

Paul 15 年前

SELECT @@IDENTITY

获取刚插入的行的标识?