Limit a Left Join on the first table

Question

I have two tables: gems and gemdetail that are left joined. I am trying to limit the LEFT JOIN to 10 records in the gems table. There are 2 other tables joined (gemreply and use

Answer 1

Try this:

SELECT g.gemid, g.title, r.tot, gemdetail.filename
FROM (SELECT * FROM gems WHERE grade = '7' LIMIT 10) g
LEFT JOIN (SELECT gemid, COUNT(*) AS tot FROM gemreply GROUP BY gemid) r
          ON r.gemid = g.gemid
LEFT JOIN gemdetail ON g.gemid = gemdetail.gemid
LEFT JOIN users ON g.userid = users.userid
ORDER BY g.gemid;

This should work.