Java Hibernate: Passing current row id to Subquery

Question

I have two Objects

Post {
   long id
   String post
   Date lastUpdate
}

Tracker {
   User user
   Post post
   Date viewed
}

User and Post are the composite ids for Tracker

While querying Post I want to figure out if the User has read the latest update on the Post

So the SQL should look something like this:

select count(*) as y0_
from nb_post AS this_ 
where (other_conditions) 
   or this_.lastUpdate > (select t_.viewed as y0_ from nb_post_tracker t_ where t_.post=this_.post))

My Criteria HAS to be on Post due to the other_conditions part. Is there a means to pass the current row's post.id through a DetachedCriteria or SubQuery?

When things get complicated with Hibernate, you don't have to keep trying to figure out how to get Criteria to do what you want. You could instead use a direct SQL query(`Session.createSQLQuery()`). You can still add entities to the query so that it auto populates the results. — markbernard, Jun 07 '16 at 18:32
Can I add just this part as the query? `this_.lastUpdate > (select t_.viewed as y0_ from nb_post_tracker t_ where t_.post=this_.post` — MandarK, Jun 08 '16 at 03:52

score 0 · Accepted Answer · answered Jun 09 '16 at 12:23

As per Mark's suggestion I simply went and wrote a some plain old SQL query. Would be really great if there could be some mechanisms provided OOB in Hibernate for situations where Many-to-Many mapped entities are concerned and programmers want to join the two entities.

Java Hibernate: Passing current row id to Subquery

1 Answers1