>>>>> "BAUMEISTER" == BAUMEISTER Alexandre <alex@stripped>
TB> And can you say what the cheapest way to force the use of a
TB> temporary table is? (Using ORDER BY would be too expensive.)
TB> Would a "HAVING 1=1", without a GROUP BY, work or would it be
TB> optimised away?
BAUMEISTER> I tried with an ORDER BY on one of the columns and the result was
BAUMEISTER> exactly the same. Writers on the table where locked while the
BAUMEISTER> "Sending data" !
An ORDER BY doesn't necessary force the creation of a temporary table.
(Only if you do ORDER BY on columns from more than one table)