SQL TUNING

Hi,
I am trying to tune a sql statement on Oracle 7.3.3 Unix.

The table a has 10,000 records.
It has a uniq index on reference column.

Here is the query:
select /*+ index(a a_ref) */
rowid
from a
where substr(reference,1,7) = 'Hithere';

I know the plan returns a full table scan because I am using a function (substr). Is there any way of getting round this problem so it uses the index ?

Many thanks... Received on Fri Nov 20 1998 - 12:55:38 CST