bosox makes a good suggestion; you can wrap your SQL Call builder with a Method that returns a status message or boolean value. Another technique that I've used in the past is to wrap your SQL statement with a SELECT clause like this:
SELECT
COUNT(*) AS ROW_COUNT
FROM NEW TABLE (
UPDATE
tablename
SET
field=?
WHERE
key=?
)
This makes your UPDATE statement actually return a row count of the number of rows that were updated in the table. The "NEW TABLE" is a SQL keyword that provides a representation of subset of rows updated by the UPDATE.