JPQL parameters and null values

skipper · **Joined:** Mon Nov 27, 2006 7:38 am **Posts:** 7

Hi,

Is there a good way of doing where-clauses with null values?

Comparison or arithmetic operations with a NULL value always yield an unknown value.

Hence the following does not work

Code:

SELECT e FROM Employee e WHERE e.name = NULL

It has to be

Code:

SELECT e FROM Employee e WHERE e.name IS NULL

Using named or positional parameters this becomes a problem. The code below won't work:

Code:

String myJPQL = "SELECT e FROM Employee e WHERE e.name = :name";
List results = em.createQuery(myJPQL)
                 .setParameter("name", null)
                 .getResultList();

Do I really have to create two JPQL statements to handle this issue?

Thanks,
Skipper

emmanuel · **Posted:** Mon May 14, 2007 12:19 pm

named parameters can be used multiple times in queries