John,

If your wildcard characters are always going to be at the end of your
search string (as in your "SMITH%" example), then use a "STARTING
WITH" clause instead of a "LIKE" clause.  Interbase will use the index
then, even with parameters.

Brian

On Mon, 24 Jan 2000 07:50:38 +1100, "John Manning"

I have a table (customer) which has an index on the column "surname". If I
have an IBQuery with the following SQL:

SELECT * FROM customer WHERE surname LIKE :surname

and I specify the value 'SMITH%' for the parameter 'surname' then the query
produces the correct results but does not use the index (verified through
SQL Monitor).

If I "hard code" the query as "SELECT * FROM customer WHERE surname LIKE
'SMITH%'" then it uses the index as expected.

Is there a particular trick I need to use here in order to get the query to
use the index?

Thanks,
John