Re: comparing index columns

Heikki Linnakangas <heikki@enterprisedb.com> writes:
> How about just doing a memcmp? That would be safe, simple and fast and 
> covers all interesting use cases.

You'd have to use datumIsEqual() or equivalent, and figure out what to
do about nulls.  I think it'd work though, at least for the purposes
that HOT needs.  There are failure cases; for example a previously
not-toasted index key column could get toasted due to expansion of an
unrelated data column.  But +1 for speed over accuracy here, as long as
it can never make a false equality report.
        regards, tom lane