You don't happend to load from the QVD file before or after the SQL query so QV creates syn tables for you?
Afaik there is no column resitriction as long as your machine can handle the volume.
I'm sitting here with a 100+ column wide query and it works fine even though I store straight into a QVD, dropping my sql connection and reading back the QVD to do transformations.
PS. You can floor() your timestamps instead of doing DayStart which should in theory be faster.
Alexander, thanks for your reply.
I'm not quite sure I understand your question " load from the QVD file before or after the SQL query"
This document basically just load s couple of tables and saves them to qvd files.
How do you drop the connection? Are you saying its better not to do any transformations like Date and such on the intial load to qvd?