On 13/05/14 11:44, Oliver Kohll - Mailing Lists wrote:
> The problem came when someone entered a record with no subject, but left it null. When this was copied over and
presentin both tables, the *next* time the join was done, a duplicate was created because the join didn't see them as
matching(null != null).
Maybe you can use x IS NOT DISTINCT FROM y ?
regards,
Yeb