Exclude Statement in SQL

Question

Hello StackOverflow Community,

I had a quick question on how to exclude data from an SQL database using an SQL statement. My situation is I have a user login to their profile page where they will be able to friend people. I want to display all users except themselves that are found in the SQL database.

Thanks for all the answers!

Rohan

Answer 1

How about:

SELECT * FROM people WHERE person_id != $current_user_id

Answer 2

Maybe just

SELECT *
FROM 
    Users
WHERE
    UserId <> @ThisUserId

Or using a Difference Union (The EXCEPT keyword in SQL Server, not sure about other RDBMS implementations)

SELECT *
FROM 
    Users

EXCEPT

SELECT *
FROM 
    Users
WHERE
    UserId = @ThisUserId

Answer 3

If you know what that user's unique ID is you could use something like this for example:

SELECT * FROM usertable WHERE id!='myuserid'

What I do with one of my authentication scripts is store the information for the person that is currently logged in in a variable so it would look like this in PHP:

SELECT * FROM usertable WHERE id!='check(id)'

Answer 4

select * from Foo where UserName not in ('Rohan', 'Rohan's friend', .....)

Is this useful?