On 18.01.2012 23:14, kenan...@gmail.com wrote:
The following bug has been logged on the website:Bug reference: 6401 Logged by: Kenaniah Cerny Email address: kenan...@gmail.com PostgreSQL version: 9.1.2 Operating system: Centos 6 x86_64 Description: ---- SELECT point(2, 3) IS DISTINCT FROM point(2, 3); ---- ERROR: operator does not exist: point = point LINE 1: SELECT point(2, 3) IS DISTINCT FROM point(2, 3) ^ HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts. ---- According to the docs (http://www.postgresql.org/docs/current/static/functions-geometry.html#FUNCTIONS-GEOMETRY), the "same as" operator is the ~= operator, not the = operator.
Yeah, unfortunately the code to transform IS DISTINCT FROM into the corresponding operator doesn't know about that. In fact, you might expect it to complain about missing "<>" operator, as "IS DISTINCT FROM" is really more like inequality, but the planner in fact implements it using the = operator, negating the result. That's because it's more common for datatypes to have a = operator than <>. Curiously, that's not the case with point datatype - it has a <> operator but not =.
Frankly that's such a rare corner case that I'm not very enthusiastic about fixing it. One idea would be to look up the type's b-tree sort operators, and pick the equality operator from there. But point datatype doesn't have b-tree sort operators, either, so it wouldn't help in this case.
-- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
