Re: fast defaults in heap_getattr vs heap_deform_tuple

On 2019-Feb-05, Andres Freund wrote:

> @@ -82,7 +80,7 @@ static Datum getmissingattr(TupleDesc tupleDesc, int attnum, bool *isnull);
> /*
> * Return the missing value of an attribute, or NULL if there isn't one.
> */
> -static Datum
> +Datum
> getmissingattr(TupleDesc tupleDesc,
> int attnum, bool *isnull)

This is a terrible name for an exported function -- let's change it
before it gets exported. Heck, even heap_getmissingattr() would be
better.

I notice that with this patch, heap_getattr() obtains a new Assert()
that the attr being fetched is no further than tupledesc->natts.
It previously just returned null for that case. Maybe we should change
it so that it returns null if an attr beyond end-of-array is fetched?
(I think in non-assert builds, it would dereference past the AttrMissing
array.)

--
Álvaro Herrera https://www.2ndQuadrant.com/
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