[eclipselink-users] WHERE a.bref IS NULL or a.bref.x. = v as an OUTER JO

[Markus Karg <karg@xxxxxxxxx>]

How to make a WHERE clause produce an LEFT OUTER JOIN?

 

Scenario:

 

A.bref refers to B and can be NULL.

B.x is a non-NULL field.

 

We like to write the following:

 

SELECT a.id FROM A a WHERE a.bref IS NULL or a.bref.x = v

 

The problem is that this produces an INNER JOIN between A and B.

 

We could workaround that by explicitly writing FROM A a LEFT OUTER JOIN a.bref b, but actually we wonder whether there is a different way to tell EclipseLink that the “dot” between bref.x does NOT automatically imply an INNER joint. For example, we could imagine that some annotation at a.bref might solve this?

 

Thanks!

-Markus