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
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
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
---------------------------- < 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
> my goal is to know any data that missing in table "pick" comparing to
> "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
|• Re: comparing tables -> continue||Toni||17 Oct|