Maintenance Suggestion warning is issued in the following situation:
Complete enumeration of <entity> attributes found: consider replacing with <entity>.* in <query>
You have a SQL query that is fetching all the attributes of an entity. In this situation, and in order to improve the maintenance of your application, you should use the wild card ('*').
Edit your SQL query and replace the
SELECT attr1, attr2, ...by
Double-click on the error line to take you directly to the SQL query editor where the warning was detected.