Preventing a single query from appearing in slow query log

In MySQL 5.1 and later, you can make runtime changes to the time threshold for which queries are logged in the slow query log. Set it to something ridiculously high and the query is not likely to be logged.

SET SESSION long_query_time = 20000;
SELECT ...whatever...
SET SESSION long_query_time = 2;

Assuming 2 is the normal threshold you use.