On Thu, Oct 1, 2009 at 10:04 PM, Chris <dmagick@xxxxxxxxx> wrote:
Tim Uckun wrote:If this is a common query you could probably do a multi-column index on all 3 columns (id, company_id, source_model_name) - but if company_id and source_model_name have a low number of distinct values, then it's not going to help.
If you try the multi-column index (which is a good idea), be sure that "id" is the last of the three columns, since that's the column on which you have an inequality test rather than an equality test; eg, (company_id,source_model_name,id).
--
- David T. Wilson
david.t.wilson@xxxxxxxxx
