[SOLVED] Need help with a query

[skyer2000]

Here is my table:

 

key_table

keyid  papid  userid
4 	7 	0
2 	1 	0
1 	2 	0
2 	2 	0
3 	2 	0
6 	2 	0
7 	19 	0
3 	19 	0
2 	3 	0
1 	0 	1
2 	0 	1
2 	0 	2
3 	0 	2

 

What I'm trying to figure out is how to setup a query that will check for a papid (lets say 2), get the keyid's associated to that papid (which would be 1,2,3,6), then pull all userid's that also have that keyid (which would output 1,1,2,2).

 

Any ideas on how to setup a query to do this?

[kickstart]

Hi

 

Quick play (untested)

 

Crude method:-

 

SELECT userid
FROM key_table
WHERE keyid IN 
(SELECT keyid
FROM key_table
WHERE a.papid = 2)

 

More elegant method

 

SELECT b.userid
FROM key_table a
JOIN key_table b 
ON a.keyid = b.keyid
WHERE a.papid = 2

 

All the best

 

Keith

[skyer2000]

Thanks!