On Tue, Nov 11, 2008 at 4:00 PM, Vladimir Sitnikov
<sitnikov.vladimir@gmail.com> wrote:
>
>> Yes, NULL values are not stored in the index, but you may create
>> functional index on
>
> Are you sure NULL values are not stored? btree, gist and bitmap index and
> search for NULL values.
It's not that they're not stored, it's that before 8.3 pg didn't know
how to compare to them I believe. The standard trick was to create a
partial index with "where x is null" on the table / column. 8.3 knows
how to compare them and doesn't need the partial index.