由事务并发引起的问题
Dirty Read(脏读)
Unrepeatable Read(不可重复读)<br>
Phantom Read(幻读)<br>
Spring解决方案
事务传播行为<br>
PROPAGATION_REQUIRED
PROPAGATION_REQUIRES_NEW
PROPAGATION_NESTED
PROPAGATION_SUPPORTS
PROPAGATION_NOT_SUPPORTED
PROPAGATION_NEVER
PROPAGATION_MANDATORY
事务超时
只读事务