Re: pgsql/src/test/regress/expected (opr_sanity.out)

> Add int2-vs-int8 comparison operators.  These are now necessary because
> the planner may try to generate them as a result of transitivity of the
> existing int2-vs-int4 and int4-vs-int8 operators.  In fact, it is now
> necessary that mergejoinable cross-datatype operators form closed sets.
> Add an opr_sanity regress test to detect missing operators.

I'm suprised that this required adding only one extra set of operators!
In general, would it be possible to allow the planner to reformulate the
plan using nested conversions *if* the required operator is not
available?

                     - Thomas