> so I used Expression.fromString("Book.hit = OldBook.hit");
You are on the right track with this, but you need to get your path's right.
Aside from using aliases which is a separate topic, the general concept of
expression paths is "they all must be relative to the root entity of the
SelectQuery".
So there is a relationship between Book and OldBook. Don't know what it is
called, let's assume it is "oldBookRelationship"... So then an expression can
be built like this:
Expression.fromString("hit = oldBookRelationship.hit");
Hope this helps.
Andrus
On Feb 9, 2012, at 12:33 PM, atomix wrote:
> I have another question regarding Expression in Cayenne :
>
> I want my generated SQL like so :
>
> *SELECT **
> *FROM *Book B1
> *JOIN *OldBook B2 *ON *B1.id= B2.id
> *WHERE *B1.hit = B2.hit
>
> so I used Expression.fromString("Book.hit = OldBook.hit");
>
> ... but it's not affect anything to the generated SQL, even when the String
> is wrong!!!!??
>
> Can anyone point me the way to do this kind of Query, not to metion
> SQLTemplate because I know the way to do so!
>
> Thank in advance!
