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1. Problem with "not (a, b) in (select ...)" in JPA query using Hibernate EntityManager    stackoverflow.com

Observation: This is a repost of a question I asked at the Hibernate forum but got no response. I have a simple graph structure like this (in MySQL): 

create table Node(
 ...

2. Why in JPA EntityManager queries throw NoResultException but find does not?    stackoverflow.com

Can somebody tell me the intrinsic reasons why in the JPA 1.0 EntityManager when retrieving an Object via find, you have to deal with null if not found, but when using ...

3. use of entityManager.createNativeQuery(query,foo.class)    stackoverflow.com

I would like to return a List of Integers from a javax.persistence.EntityManager.createNativeQuery call Why is the following incorrect? entityManager.createNativeQuery("Select P.AppID From P", Integer.class); specifically why do I get "...Unknown entity: java.lang.Integer" Would I have to ...

4. What does JPA EntityManager.getSingleResult() return for a COUNT query?    stackoverflow.com

What does EntityManager.getSingleResult() return for a COUNT query? So.. what is the precise runtime type of foo? 

Object foo = em.createQuery("SELECT COUNT(t) FROM com.company.Thing t WHERE prop = :param")
     ...

5. EntityManager's named query are slow where as JPAEntityManager's Expression query are faster    stackoverflow.com

I am using Weblogic 10.3 and EJB3 with TopLinks(EclipseLinks) JPA implementation. I am facing an issue with my named queries, which are performing slow. However If I use EclipseLinks JPAEntityManager's Expression ...

6. Oracle query Java EE, Entity Manager    stackoverflow.com

If I have an Oracle database, with structure, SCHEMA/TABLE1 SCHEMA/TABLE2 and I want to create a query to select all rows from Table1, would it be, "Select x from SCHEMA.TABLE1 x"

7. JPA - Entity Manager Query    coderanch.com

8. Avoid query binding on EntityManager initialization    forum.hibernate.org

Hi to all, this is my first post here, and i want to say that this forum looks awesome, it has a lot of content. I have the next situation: I'm working on struts 2 application with Hibernate JPA, so i defined a custom interceptor to initialize an EntityManager if is null or something like that, but i see that when ...