On Thu, Nov 12, 2009 at 13:55, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> I'd go for the first of those, for sure. Testing attnotnull is
> significantly cheaper than enforcing a generic constraint expression,
> and NOT NULL is a sufficiently common case to be worth worrying about
> optimizing it.
When I looked at doing this, I thought about just using check
constraints just for the book keeping and leaving attnotnull as it is.
If would be easier, but it seemed quite ugly.