selecting userid that is not in other table

[abs0lut]

I need to select userid from tblusers that is not in tbltopics.

could you please help me?

[cooldude832]

something like

SELECT T1.UserID as UserID 
FROM `tblusers` as T1
WHERE T1.UserID !IN(SELECT UserID FROM `tbltopic`)

 

[fenway]

something like

SELECT T1.UserID as UserID 
FROM `tblusers` as T1
WHERE T1.UserID !IN(SELECT UserID FROM `tbltopic`)

 

Not really.

 

You need to use a LEFT JOIN... IS NULL... but we'll need the table structure to be sure.