On 02.09.2011 16:30, Philip Martin wrote: > Bert also suggests changing our other indices by adding wc_id and/or > local_relpath thus allowing them to be UNIQUE. Can anyone confirm that > UNIQUE indices are better?
Just imagine, if the UNIQUE constraint did not imply an index, every INSERT or UPDATE would have to scan the whole table in order to verify the constraint. That would be ... less than efficient. -- Brane
