通过上面的实验可以发现,当参数completion_type设置为2时,COMMIT WORK后,我们再执行select @@version,会出现ERROR 2006(HY000):MySQL server has gone away的错误,这其实就是因为当前会话已经在上次执行COMMIT WORK语句后与服务器断开了连接。 ROLLBACK和ROLLBACK WORK与COMMIT
We can run multiple SQL statements in a single transaction by grouping them within the pair of statements START TRANSACTION and COMMIT or ROLLBACK. However, we can’t nest transactions. COMMIT, ROLLBACK, and SAVEPOINT are SQL transaction management statements in MySQL. However,only the transactiona...
事务控制语句 ,begin,rollback,savepoint,隐式提交的 SQL语句 事务控制语句 在MySQL命令⾏的默认设置下，事务都是⾃动提交的，即执⾏SQL语句后就会马上执⾏COMMIT操作。因此开始⼀个事务，必须使⽤ BEGIN、START TRANSACTION，或者执⾏SET AUTOCOMMIT=0，以禁⽤当前会话的⾃动提交。这和Microsoft SQL ...
可以看到,插入第二记录1时,因为重复的关系抛出了1062的错误,但是数据库并没有进行自动回滚,这时事务仍需要我们显式地运行COMMIT或者ROLLBACK。 另一个容易犯的错误是ROLLBACK TO SAVEPOINT,虽然有ROLLBACK,但是它并不是真正地结束一个事务,因此即使执行了ROLLBACK TO SAVEPOINT,之后也需要显式地运行COMMIT或者ROLLBACK...
开启一个事务需要将SQL命令用BEGIN和COMMIT命令包围起来 BEGIN;UPDATEaccountsSETbalance=balance-100.00WHEREname='Alice'; SAVEPOINT my_savepoint;UPDATEaccountsSETbalance=balance+100.00WHEREname='Bob';--oops ... forget that and use Wally's accountROLLBACKTOmy_savepoint;UPDATEaccountsSETbalance=balance+100.00WH...
Products table.INSERTINTOProducts(ProductID,Name)VALUES(101,'Laptop');SAVETRANSACTIONSavePoint1;-- Create a savepoint.-- Insert data into the Suppliers table.INSERTINTOSuppliers(SupplierID,Name)VALUES(201,'Tech Corp');-- Rollback to the savepoint if needed.ROLLBACKTRANSACTIONSavePoint1;COMMIT...
TheSQL SAVEPOINTstatements do not affect locks assigned to the transaction. In particular, these SQL statements do not release any locks. Locks are only released byCOMMITorROLLBACK. Subtransactions are particularly useful for keeping the effects of database procedures atomic in the sense that they ...
In[3]:= Begin a transaction: In[4]:= Insert data: In[5]:= Set a savepoint: In[6]:= Out[6]= Insert more data: In[7]:= Roll back to the savepoint: In[8]:= Commit the transaction: In[9]:= The table only contains data inserted up to the savepoint: In[10]:= Out[10...
All savepoints of the current transaction are deleted if you execute a COMMIT, or a ROLLBACK that does not name a savepoint. A new savepoint level is created when a stored function is invoked or a trigger is activated. The savepoints on previous levels become unavailable and thus do not...
示例 建立并随后销毁一个保存点: BEGIN; CREATE TABLE IF NOT EXISTS table1 (a int,b int); INSERT INTO table1 VALUES (3); SAVEPOINT my_savepoint; INSERT INTO table1 VALUES (4); RELEASE SAVEPOINT my_savepoint; COMMIT; 相关链接 SAVEPOINT,ROLLBACK TO SAVEPOINT父主题: TCL语法 上...