return PointerGetDatum(v->val.numeric); should be something like PG_RETURN_NUMERIC(v->val.numeric); ?
Thanks for this reminder, a new patch is attached. and commitfest
entry is added as well[1]. For recording purposes, I compared the
new operator with all the existing operators.
select 1 from tb where (a->'a')::numeric = 2; 30.56ms select 1 from tb where (a->>'a')::numeric = 2; 29.43ms select 1 from tb where (a@->'a') = 2; 14.80ms
I don't like this solution because it is bloating operators and it is not extra readable. For completeness you should implement cast for date, int, boolean too. Next, the same problem is with XML or hstore type (probably with any types that are containers).
It is strange so only casting is 2x slower. I don't like the idea so using a special operator is 2x faster than common syntax for casting. It is a signal, so there is a space for optimization. Black magic with special operators is not user friendly for relatively common problems.
Maybe we can introduce some *internal operator* "extract to type", and in rewrite stage we can the pattern (x->'field')::type transform to OP(x, 'field', typid)
