On 10/10/2014 02:04 AM, Peter Geoghegan wrote:
> I found a reference made obsolete by commit 9e85183b, which is from
> way back in 2000.
>
> comparetup_index_btree() says:
>
> /*
> * This is similar to _bt_tuplecompare(), but we have already done the
> * index_getattr calls for the first column, and we need to keep track of
> * whether any null fields are present. Also see the special treatment
> * for equal keys at the end.
> */
>
> I think that this comment should simply indicate that the routine is
> similar to comparetup_heap(), except that it takes care of the special
> tie-break stuff for B-Tree sorts, as well as enforcing uniqueness
> during unique index builds. It should not reference _bt_compare() at
> all (which is arguably the successor to _bt_tuplecompare()), since
> _bt_compare() is concerned with a bunch of stuff highly specific to
> the B-Tree implementation (e.g. having a hard-wired return value for
> comparisons involving the first data item on an internal page).
Yeah. Want to write that into a patch?
- Heikki
