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). -- Peter Geoghegan -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
