Null « Field « JPA Q&A

1. Strange JPA behaviour, initialized field is null stackoverflow.com

I'm observing a very strange behaviour with an entity class and loading an object of this class whith JPA (hibernate entitymanager 3.3.1.ga). The Class has a (embedded) field, that is initialized ...

2. Null vs empty field in database stackoverflow.com

I have database in which data is imported from the other table. if data is empty there. so while importing to here it became null. When i query the columns like, ...

3. Hibernate Postload and null fields on referenced entities stackoverflow.com

I have two entities like the ones below:

@Entity
public class Project {
   @Id
   private id;
   private String name;

   ...
}

@Entity
public class Person {
   ...

4. 0 x N in hibernate (null values in a FK field) coderanch.com

Hi, Let's consider the following example: One Client may have from 1 to N Cars. One car may belong to 0 or 1 Client. It's then a 1 x N relationship, and the Car table will have the ClientID field as an FK. Since it is an optional relationship, it's totally acceptable that the FK in the Car table will accept ...

5. Update not null fields forum.hibernate.org

Hello, I have a problem with the update of an entity. Let's say i have a db with columns id | content | date and an entity Question with fields id, content, date I have the annotation @org.hibernate.annotations.Entity(selectBeforeUpdate = true, dynamicUpdate = true) When i populate my entity, let's say that date is null, but in db it has already a ...

6. How to set a field value to null? forum.hibernate.org

I am using JBoss3.2.6 with Hibernate 2.1.6. Everything is OK,But when I want to set a field in my table to null, it fails to do so. My code goes like: Code: Session session =HibernateContext.getSession("java:/hibernate/MySessionFactory"); List list = null; try { list = session.find("from EseExperimentUser as eeu where eeu.UserId ...

7. Example: excluding null/empty fields forum.hibernate.org

Hi, I'm using Hibernate 2.1.7 and have a question about the Example class for constructing Criteria queries. Normally Example excludes properties that are null. I would like to also exclude properties that are empty strings, since empty strings may be coerced to NULL in Oracle. This is fairly easy to do with my own Example.PropertySelector, but I was wondering if there ...

8. how to apply math function if field is null forum.hibernate.org

9. Problems with null id field in SqlServer 2005 forum.hibernate.org

WARNING: I'm very new to hibernate and just going through basic tutorials. I'm going through chapter 2 tutorial from THE book as recommended in the quick start documentation. However, I substituted HSQL with SqlServer 2005 database, and changed nextMessage to just a simple Long. mapping: ...

10. Set only non-null fields on update? forum.hibernate.org

(I am constructing a dialogue with myself in here, but oh well) ... so I guess the issue here is that the dynamic-update will update only those fields that have changed. That is not exactly what I want -- what I want is a way to update only those fields that are non-null. Is there a way to do this with ...

11. One to one null or field value forum.hibernate.org

Hi all, I am HB-Newbe. Problem seems easy, only 2 tables to make a select: table person and table persondetails, 1:1, both with same ids as pk, in hybernate i made annotation one to one. Initially most persons have not a associated persondetail in the db. I want get a list of all persons who have a specific field in persondetails ...

12. Date_created field value is set to NULL instead of NOW() forum.hibernate.org

Hi all, When I use hibernate in my spring project the "NOW()" function of my "date_created" fields doesn't seem to work. I just get a NULL value instead of the NOW() value. When I insert a row (via my phpMyAdmin) manually it does work ok, and the date_created field gets filled with the NOW() result though. Code: INSERT INTO `autopermit`.`family` ( ...