Transaction isolation mechanism in MySQL

0. Read uncommitted (read uncommitted transaction data-dirty read)

1. Read committed (Only the transaction data can be read and committed-the transaction data cannot be read repeatedly)

2. Repeatable read (New data can be read only when both transactions are committed-Phantom read)

3. serializable (Only one transaction can operate on data, whether read/write or other transactions wait)

Set session | global transaction isolation level

Read uncommitted
| Read committed

Repeateable read
| Serializable

Select @ tx_isolation view current isolation level (Session)

Select @ Global. tx_isolation
View global isolation levels

Http://xm-king.iteye.com/blog/770721

Http://orzdba.wordpress.com/2011/03/03/transaction_isolation_levels/