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Hibernate HQL still requires 'is null" in queries?

Zone: Java Programming Language

Tags: nvl, hql, hibernate

One thing that I always hated about SQL was that I always needed two versions of a query if one of the values needed to be tested against null. Yes, there is the nvl() function, but my understanding is that it's not very efficient to write queries with it and it requires an in-band value to be used which may not be possible in some cases.

I was disappointed that Hibernate continues this practice in HQL. Why must I create the following two versions of an HQL query? Or do I? Is there a way to write HQL such that it'll effectively combine the following two queries in a way that's no less efficient in terms of query execution speed?

QUERY #1 FOR WHEN objTypeId IS NULL:
      from com.knowlist.list.hh.UserPrivilege
      where
            unum=:unum
            and privId=:privId
            and objTypeId is null

QUERY #2 FOR WHEN objTypeId IS NOT NULL:
      from com.knowlist.list.hh.UserPrivilege
      where
            unum=:unum
            and privId=:privId
            and objTypeId = :objTypeId

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6.4

Question Stats

Zone: Programming

Question Asked By: HappyEngineer

Solution Provided By: modulo2

Participating Experts: 3

Solution Grade: C

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Comment by codecln

Hi,
I have the same issues. I mean executing nvl() in Hql is there any solution for keeping the functionality in HQL rather seeking for native SQL.

Kind reply is accepted...
With Regards
Pugazh

20080723-EE-VQP-34