Query help
 

I have a table with (for simplification) three columns: fromuserid, touserid, and amount. I want to find the sum of amount, but it is governed by the following (using 13 as a sample userid):

1. If touserid is 13, then add the amount to the sum
2. If fromuserid is 13, then subtract the amount from the sum

How would I do this?

Why not do your calculations outside of the query using PHP - makes for faster processing time :)

[SQL]SELECT SUM(IF(fromuserid = 13, -1, 1)) FROM table WHERE fromuserid = 13 OR touserid = 13[/sql]

that should work i think

Close, got it working with this, thanks:
[sql]
SELECT sum(IF(touserid = 13, amount, - amount))
FROM turtledollar
WHERE touserid = 13 OR fromuserid = 13
[/sql]

oops, i forgot that you ahve a special col with the ammount ;)