Mysql advanced transactions

Mysql advanced transactions

Generally speaking, a transaction refers to a group of operations, either successfully executed or not executed. ----> atomicity

Before all operations are completed, other sessions cannot see the process of intermediate changes-> isolation

Before and after a transaction occurs, the total amount of data still matches -----> consistency

Transaction impact cannot be undone ------> persistence

If an error occurs, the transaction cannot be undone and can only be undone through "compensatory transactions"

Transfer

Li San: ---> spending 500, Li San-500

Zhao 4: ----> received 500, Zhao 4 + 500

About the transaction engine:

Select innodb/bdb

Start transaction: start transaction;

SQL ....

SQL ....

Submit

Rollback

Note: when a transaction commit or rollback ends

Note: Some statements may cause implicit transaction commit, such as start transaction.

A specific example of a transaction: