help on date column

Hi,
    I have created an index for a date column in a table. This column is nullable. How do I form up a query so that this query will make use of the index ? I need to select all the rows which have the date field null.

     select col1, col2  from table_a where sdate is null;

This does not make use of the index. So is there a way to avoid doing a full table scan?

    Thanks & regards! Received on Thu Sep 25 1997 - 00:00:00 CDT