mysql transaction

1) See which engines support transactions:

SQL: Show engines;

2) View the table engine type:

Show create table table_name;

3) Check if it is automatically submitted:

show variables like ‘%autocommit%’;

4) The method of transaction start:

a) mysql_autocommit(0); If the program is coredump here, please check if connect db

b) SQL:Set autocommit=0;

c) Begin work;

d) Start transaction;

5) The method of the end of the transaction:

a) SQL:Commit/rollback

b) Mysql_commit/mysqlrollback

c) Implicit transaction, refer to http://blog.csdn.net/blues1021/article/details/6329190


Concurrent transactions:

Lock Mechanism:

Optimistic locking: controlled by the where condition, controlled by the value of the version field or custom field;

The number of rows affected by update : the return value of mysql_affected_rows , which can be used to determine whether the transaction is terminated

Pessimistic lock = exclusive lock

Select  * from table for update;




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