[castor-dev] Problem with absolute/size on QueryResults

[Paul Danckaert]

Greetings,

I was testing the absolute positioning on QueryResults in conjunction with the size, and found the results to be rather interesting.  What appears to be happening is that when you have a parent/child dependent object relationship, the size and the positioning reflect the SQL JOIN'ed query results rather than the parent object results, even though you are iterating over just the parent object in the results.

As an example, if I have a Master object that contains one or more Detail dependent objects in the following configuration:

master id1 has detail dt1,dt2,dt3
master id2 has detail dt4,dt5,dt6

My join'ed query results look something like:

id1 | dt1
id1 | dt2
id1 | dt3
id2 | dt4
id2 | dt5
id2 | dt6

In this situation, my straight SQL result set size is 6, but my count of Master objects should be 2.  So, in a OQL query like:

SELECT master from test.Master

Should I expect to get a size of 6 or 2?  I get 6, but I would expect to get 2, as there are actually only two items in the results.  (If you perform the actual iteration with .hasMore() and .next() you will only get two objects back.)

I believe that if I removed the depenent object mapping, I would probably get the correct size, since we wouldn't have the JOIN confusing the row count.

Extending this problem, if we then look at calling absolute on the QueryResult's, it gets pretty interesting.  The absolute call positions itself into the results above, which means your absolute position is fairly random, and you can actually absolute position yourself from 1 to 6, as opposed to from 1 to 2. 

So, what should the expected behavior be of size and absolute?  I didn't read anything in the API reference about it being limited to simple objects without relationships, but that seems to be the behavior that I'm seeing.  Its certainly possible I'm doing this wrong, so I would be glad to hear of it working properly in this situation.  I'm running against a Postgres database, using both the postgres supplied drivers as well as the castor supplied drivers.  I'm also using Castor 0.9.4.1.

I have tested a straight JDBC query and iteration, and absolute works the way its expected to.  In fact, absolute does work in the castor test, but its absolute referenced into the joined results, which makes it a pretty confusing set to iterate through.

Thanks for any help on this,

paul



pgsq/0941