when do we call entity manager flush and refresh methods

[mravikrish]

Hello,

I am ramu, i am confused with the entity manager methods flush and refresh. exactly when we need to call these methods. while persisting entities.

Thank you
KRamu

[jaikiran]

The Entitymanager javadoc might help http://java.sun.com/javaee/5/docs/api/javax/persistence/EntityManager.html

In brief - the flush call will issue SQL queries to update the database with the changes that have been done to the in memory entities. The refresh on the other hand pulls the entity state from the database and overwrites the in memory changes.