On 4 March 2010 17:26, Terry <td3...@gmail.com> wrote: > I have 4 tables: dsclient_logs,backup_sets,dsbox,customer. I want a > query that will return all rows from dsclient_logs, insert two columns > from the customer table, and one column from backup_sets. The > relation is this: > > dsclient_logs.userid = dsbox.dsbox_snum AND backup_sets.box_id = > dsbox.box_id AND dsbox.account_num = customer.account_num > > I originally had this: > > SELECT * FROM > (SELECT > dsclient_logs.ev_id,dsclient_logs.type,dsclient_logs.ev_time,dsclient_logs.category,dsclient_logs.error,dsclient_logs.ev_text,dsclient_logs.userid,dsclient_logs.ex_long,dsclient_logs.client_ex_long,dsclient_logs.ex_text,dsclient_logs.timestamp,backup_sets.set_name,customer.company_name,customer.account_num > FROM dsclient_logs,dsbox,backup_sets,customer > WHERE dsclient_logs.userid = dsbox.dsbox_snum AND backup_sets.box_id = > dsbox.box_id AND dsbox.account_num = customer.account_num > ORDER BY dsclient_logs.ev_id desc > LIMIT 101) as a > ORDER BY ev_id > > In the end, I want a single row for each ev_id that has the > account_num, company_name, and backup_sets filled in. I have a > feeling this needs to be done with a different type of join. Horrible > explanation so I apologize and will gladly redefine my question upon > some feedback. > > I think you want an INNER JOIN. This won't match if any 1 table doesn't match on the join.
SELECT dsclient_logs.ev_id,dsclient_ logs.type,dsclient_logs.ev_time,dsclient_logs.category,dsclient_logs.error,dsclient_logs.ev_text,dsclient_logs.userid,dsclient_logs.ex_long,dsclient_logs.client_ex_long,dsclient_logs.ex_text,dsclient_logs.timestamp,backup_sets.set_name,customer.company_name,customer.account_num FROM dsclient_logs INNER JOIN dsbox ON dsbox.dsbox_snum = dsclient_logs.userid INNER JOIN backup_sets ON backup_sets.box_id = dsbox.box_id INNER JOIN customer ON customer.account_num = dsbox.account_num ORDER BY dsclient_logs.ev_id desc If one side can be missing, you'd use a LEFT JOIN. For example, if backup_sets is only sometimes present, and you still want to return data in these instances, just use LEFT JOIN backup_sets. Regards, Thom
