Transaction Control Language (TCL)

Sql statement or a group consisting of one execution unit, the execution unit performs either all, or all not be executed. Such as: transfer.

Atomicity (Atomicity): a transaction are either executed or rolled back (not subdivided)

Consistent operation before and after the operating state ensure data: Consistency (Consistency)

Isolation (Isolation): When multiple transactions simultaneously operate on the same data in the same database, a transaction is not executed a transaction otherwise interfere

Persistent (Durability): Once a transaction is committed, the data is persisted to the local (data will be permanent changes to the database), unless other transactions modify

Step transaction

1、开启事务
2、编写事务的一组逻辑操作单元（多条sql语句）
3、提交事务或回滚事务

Step # demonstrate the use of a transaction to transfer :( for example) 
# open transaction 
the SET autocommit = 0 ; 
Start Transaction; 
# to prepare a set of transaction statements 
Update the Account the SET Balance = 500  the WHERE usename = ' Wuji ' ; 
Update the Account the SET Balance = 1500  the WHERE usename = ' Guo Xiang ' ; 
# end transaction 
commit;

Affairs Category:

Implicit transaction, there is no obvious sign of opening and end of the transaction

insert, update, delete statement itself is a transaction

Flag explicit transaction, with a clear opening and closing of the transaction

Prerequisite: Cancel automatic submission function
    SET the autocommit = 0 ;
     . 1 , open transaction 
    start transaction; may be omitted 
    2 , prepared by a set of logical operations of the transaction units (multiple sql statement) 
    INSERT 
    Update 
    Delete 
    provided rollback point: savapoint rollback named; 
    3 , commit the transaction or roll back the transaction 
    submitted to: commit; 
    rollback: rollback; 
    rollback to the designated place: rollback to roll back the roll call;

Use the keyword

SET the autocommit = 0 ; 
Start Transaction; 
the commit; 
ROLLBACK; 

that the savepoint breakpoint 
commit to break 
rollback to break

reference:

https://www.jianshu.com/p/6738c4b11da8