Fernand St-Georges (fernand.st-georges@videotron.ca) writes:
> I have 16,000 rows in tblClient and 3000 rows in NewTable.
>
> SELECT tblClient.*
> FROM tblClient INNER
> JOIN [New Table] ON tblClient.NoDossier <> [New Table].NoDossier
>
> if I use = (equal) instead of <> (exclude), the query returns 3000 rows
>
> when I use <> it returns 160000 rows,
> if I try group by, the query bugs
>
> what is my problem

Using <> as a joining operator is very rarely useful. Say that the number
of rows in tblClient is 163 and in [New Table] have 1000 rows. That makes
up for a total of 163000 possisble combinations. You condition filters out
those 3000 where NoDossier are equal.

What you probably want is:

SELECT c.*
FROM tblClient c
WHERE NOT EXISTS (SELECT *
FROM [New Table] n
WHERE c.NoDossier = n.NoDossier)

--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techinf...2000/books.asp