I wrote:
> I have plans to revise the handling of join variables at some point
> in the future, probably as part of the fabled querytree redesign.
> And mergejoining on expressions should be allowed too, sooner or later.
> Neither one is going to happen for 7.2 though ...
There probably ought to be something in the master TODO list about
these. Bruce, would you add something along the lines of:
* Nested FULL OUTER JOINs don't work (Tom)
* Allow merge and hash joins on expressions not just simple variables (Tom)
regards, tom lane
