Re: question, about mysql query

This isn't a PHP question at all. It's a MySQL question. However, answers are below, with forwards to the appropriate lists for archiving purposes. On Mon, Jun 2, 2008 at 9:19 PM, LKSunny <ad@pc86.com> wrote: > two table, tablea and tableb > tablea > uid, col1, col2, col3 > 1, xx, xx, xx > 2, xx, xx, xx > 3, xx, xx, xx > tableb > id, uid, col1, firstdata > 1, 1, xx, 1 > 2, 2, xx, 0 > 3, 2, xx, 0 > 4, 1, xx, 0 > > i want query tablea, and join tableb, uid is associate, ok "LEFT JOIN > tableb b ON a.uid = b.uid", and than i want tableb > firstdata=1 or tableb > no associate uid "b.firstdata=1 OR b.uid IS NULL", by the time all ok, but i > want add one case, if tableb firstdata all is 0, result one row, like b.uid > IS NULL, i don't know how to > > i want result is all tablea data no double, tableb one case firstdata is 1 > (one uid in tableb just one row possible is firstdata=1), or no row in > tableb, or all firstdata = 0 > > Thank You Very Much !! > > This query can't > SELECT a.*, b.* FROM tablea a LEFT JOIN > tableb b ON a.uid = b.uid WHERE > (b.firstdata=1 OR b.firstdata=0 OR b.uid IS NULL) Okay, I had a difficult time understanding what it is you need, but hopefully got enough from your message to be able to help you out. What I think you may be looking for is something like this: SELECT * FROM tableb WHERE firstdata='1' AND id IN (SELECT DISTINCT id FROM tablea ORDER BY id ASC); That will select only unique id columns from tablea and select only the rows from tableb where the id columns match and firstdata is set to '1'. You can then modify that query as needed. -- </Daniel P. Brown> Dedicated Servers - Intel 2.4GHz w/2TB bandwidth/mo. starting at just $59.99/mo. with no contract! Dedicated servers, VPS, and hosting from $2.50/mo.