Today for the first time
now I had to use @SqlResultSetMapping. While everything works well there so
far, there still is one issue I would like to solve. Possibly you can help me.
:-)
I am executing a typical master-detail JOIN:
SELECT Master.PK_A, Detail.PK_B FROM Master JOIN Detail ON
(Master.PK_A = Detail.FK_A) WHERE Master.X = ? AND Detail.Y = ?
The result is exactly what I expected: A table containing
all details having Y = ? and their corresponding masters.
But actually I want to get not fields but entity instances,
so I added SqlResultSetMapping for Master and Detail, which both are annotated
with @Entity, @Table, @Column, etc.
The result is not exactly what I want get…: The "AND
Detail.Y = ?" has no effect on that details linked with each master.
When iterating over the Master.details collection which was
automatically filled by TopLink behind the scenes thanks to the @OneToMany
relationship, I notice that ALL the master's details are contained - not just
those with actually "Detail.Y = ?" as expected. Looking at the SQL
TopLink does, it is rather clear why: The linked details are not filled from
just my SQL's ResultSet, but actually TopLink executes another (automatically
created) SQL to get ALL details per Master.
This is not what I want.
How to tell TopLink that it shall populate the linked
details of each master with just the rows found in MY OWN SQL but not execute
an unfiltered one?
Thanks!
Markus