Spring five transaction isolation levels and seven transaction propagation behavior

The five transaction interval levels are: Lsolation property values

1,default

Default transaction ISOLATION LEVEL

2,read_uncommitted

READ UNCOMMITTED, one transaction can operate another uncommitted transaction, cannot avoid dirty read, non-repeatable read, Phantom read, isolation level is lowest, concurrency performance is highest

3,read_committed

Read Committed, one transaction can not operate another uncommitted transaction, can prevent dirty read, cannot avoid non-repeatable read, Phantom read.

4,repeatable_read

Be able to avoid dirty reading, non-repeatable reading, cannot avoid phantom reading

5,serializable

Highest isolation level, lowest resource consumption, highest cost, ability to prevent dirty reads, non-repeatable reads, Phantom reads.

Propagation behavior of seven transactions

1,propagation_required

If a transaction exists, the current transaction is supported, and if it does not exist, a new transaction is created

2,propagation_supports

If a transaction exists, the current transaction is supported and the non-transactional method runs if it does not exist

3,propagation_mendatory

If a transaction exists, the current transaction is supported, and if present, an exception is thrown

4,propagation_requires_new

Always open a new transaction, suspend the transaction if the transaction exists

5,propagation_not_supported

The total non-transactional method runs and suspends all transactions

6,propagation_never

The total non-transactional method runs, and throws an exception if the transaction exists

7,propagation_nested

A transaction exists, it is run in a nested transaction