Thank you Peter, it does work, I have some question again if you don't mind. Let say i have similiar tables like before, but i will add another field for "pick". They will become like this :
Table "Master" Table "Pick" m p q ----- ------ a a x b b x c c x d d x e b y f g y g now, the goal is to know any data that missing in table "pick" wearing atribut "y" (b,g) comparing to table "master". The answer should be "a,c,d,e,f". Would you please once again help me to modify the query before? FYI, I try to add some conditional phrase : select m from master left join pick on master.m = pick.p where pick.q = 'y' and pick.p is null but it doesn't work. oh ya, I use MySQL 3.23.45 thank you so much Toni ---------------------------- < finish > ----------------------- Toni wrote : > i have a problem to compare data inside two tables. i have two tables let > say: "Master" and "Pick". For example the content of these two tables are: > > Table "Master" Table "Pick" > a a > b b > c c > d d > e > f > g > > my goal is to know any data that missing in table "pick" comparing to table > "master". The answer should be "e, f, and g". Would you help me to show me > the query? > > thank you so much .. Assuming field m in master and p in pick... SELECT m from master LEFT JOIN pick on master.m=pick p WHERE pick.p IS NULL PB --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php