Question

Note: Using MySQL 4.0, which means no subqueries (at present).

I have 2 tables:

• A ‘user_details’ table
• A ‘skills’ table, which has the user_id and a ‘skill_id’, which maps to a predefined set of skills defined elsewhere.

The current query allows an admin to search for users by selecting skills, and the query works in an OR fashion, eg:

LEFT JOIN skills  ON (ud.user_id = skills.user_id)   WHERE skills.skill_id in (51, 52, 53, 54, 55) GROUP BY ud.user_id 

This returns too many records and thus I want this search field to work in an AND fashion, where a user must have ALL the selected skills to be returned in the search.

It may be possible to get MySQL upgraded if subqueries are the best option.

edit: Something to do with group by, count, having etc. Can you restrict a group by command with a requirement on how many matched rows you return? (eg 5 in this example).

edit2: Testing out:

HAVING COUNT( * ) > 5 

Answer 1

You don’t need a subquery or a join.

SELECT user_id FROM skills WHERE skill_id IN (51, 52, 53, 54, 55) GROUP BY user_id HAVING COUNT(*) = 5;