Never use a FILTER on a grid. See http://www.craigberntson.com/blog/2008/08/dont-filter-data-in-grid.asp

>Surely an old question :) ...
>
>I have a file of about 500,000 records - file is about 40Mg in size.
>Records belong to 1 of 5 possible groups identified by a 20 char string field.
>There are about an equal number of records per group i.e. +/-100,000 per group.
>I want to allow the user to see only one chosen group of records at a time in a scrollable grid which has 3 colums.
>
>What is the fastest way to accomplish this? SET FILTER seems sluggish but perhaps I am not using it in the right way.
>
>TIA