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subselect fetching ignores max results

Description

When maxResults is set for a query, the hibernate subselect fetching strategy ignores it. For example, I have a class entry, that has a list of comments, which are configured to use the subselect fetching strategy. You can see that in the original query, only the top ? results are fetched:

select
top ? entry0_.id as id0_,
entry0_.title as title0_,
entry0_.entry as entry0_,
entry0_.time as time0_,
entry0_.category_id as category5_0_
from
Entry entry0_
order by
entry0_.time desc

But then when it does the sub select query to lazily load the comments, this is the query it runs:

select
comments0_.entry_id as entry5_1_,
comments0_.id as id1_,
comments0_.id as id1_0_,
comments0_.time as time1_0_,
comments0_.comment as comment1_0_,
comments0_.author as author1_0_
from
Comment comments0_
where
comments0_.entry_id in (
select
entry0_.id
from
Entry entry0_
)
order by
comments0_.time desc

So, it loads every single comment in the database, even though only the comments for the top ? entries are needed. Of course, if there was no order by clause on the first query, the sub select may not return the same results, so it should probably only do this when there is an order by clause in the first query, and it should make sure it includes the order by clause in the sub select.

Environment

Hibernate 3.2.1 HSQLDB 8.0

Status

Assignee

Unassigned

Reporter

James Roper

Components

Affects versions

3.2.1
3.5.3

Priority

Minor