I was learning some JPA to teach to some java friends and I was wondering, how do you handle updates that comes after the creation of the db in JPA? Let\'s say I have a production environment where th
When I execute: public void beginTransaction() { em.getTransaction().begin(); } following an active transaction started in the same way, I get the following exception:
My current persistence.xml table generation strategy is set to create. This guarantees that each new installation of my application will get the tables, but that also means that everytime the applicat
Using the EclipseLink JPA2 implementation (not sure if it\'s the same with the Hibernate implementation)
The following code throws an exception when invoking \"em.refresh(p)\": 1: EntityManager em = emf.createEntityManager();
I am trying to do a simple persistence with jpa 2.0 and derby but I keep getting a NullPointerException.
I am trying to implement the following convenience method: /** * Counts the number of results of a search.
I am facing issues while retrieving data for entities having bi-directional many-to-many relationship. If I use List for storing entities, I get unable to fetch multiple bags simultaneously error. If
I want to cleanup the database after every test case without rolling back the transaction. I have tried DBUnit\'s DatabaseOperation.DELETE_ALL, but it does not work if a deletion violates a foreign ke
I have a MySQL database with many databases, each named for a specific customer. A webapp is deployed per customer. The name of the webapp determines the underlying database name. When the webapp sta
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