While preparing an improved treatment of constant columns ("[fake_]project's"), I noticed that there seems to be some obsolete code that assumed that (loop-lifted-)staircasejoin resukts were not "pruned"; removing this code does not seem to do any harm (at least all tests still work), but it reduces/simplifies the generated code considerably.
While preparing an improved treatment of constant columns ("[fake_]project's"),
I noticed that there seems to be some obsolete code that assumed that
(loop-lifted-)staircasejoin resukts were not "pruned";
removing this code does not seem to do any harm (at least all tests still work),
but it reduces/simplifies the generated code considerably.

These changes are required for the following [fake_]project related improvements.

zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb