I have written some patches which add support for NULLs to Postgres95.
In fact support for NULLs was already present in postgres, but it had been
disabled because not completely debugged, I believe. My patches simply add
some checks here and there. To enable the new code you must add -DNULL_PATCH
to CFLAGS in Makefile.global. After recompiling you can do things like:
insert into a (x, y) values (1, NULL);
update a set x = NULL where x = 0;
You can't still use a "where x=NULL" clause, you must use ISNULL instead.
This could probably be an easy fix to do.
Submitted by: Massimo Dal Zotto <dz@cs.unitn.it>
Select queries with an isnull or notnull clause, like "select * where
somefield isnull", crash the backend if the table has at least one index.
If the indices are deleted the queries work again. Also the explain
command fail in the same way.
The is caused by a bug in subroutine of the optimizer which doesn't check
null values in the clauses.
Submitted by: Massimo Dal Zotto <dz@cs.unitn.it>
This is a patch to prevent an endless loop occuring in the Postgres backend
when a 'warning' error condition generates another warning error contition
in the handler code.
Submitted by: Chris Dunlop, <chris@onthe.net.au>
It is not possible to define attributes as arrays of date or time, the
type _time and _date are not defined.
Submitted by: Massimo Dal Zotto <dz@cs.unitn.it>
The type _char16 (array of char16) is incorrectly defined as array of name
and values longer than 16 chars are stored as names and not truncated to 16
bytes as they should be.
Submitted by: Massimo Dal Zotto <dz@cs.unitn.it>
before (plus some optimisations/bug fixes et al). I've included a small
demo transcript below. Note that all of of the display
functionality/intelligence you see here, can be had merely by calling
the new LIBPQ PQprint() routine with the appropriate arguments/options,
including the HTML3 output guff.
submitted by: Julian Assange <proff@suburbia.net>
varchar.diff
------------
This patch was necessary for the OpenLink Postgres Database Agent.
I think this fixes a bug anyway.
The following query demonstrates this bug:
create table foo (bar varchar);
insert into foo values (''); -- no problem
select * from foo where bar = ''; -- fails
causes segmentation fault.
Thanks to: Salvador Ortiz Garcia, Robert Patrick, Paul 'Shag' Walmsley,
and James Cooper for finding and fixing the problem.
Marc G. Fournier