Summing up data from a table

Article:		Self-Inflicted SQL
Subject:		Summing up data from a table
Date:		2004-10-19 03:55:35
From:		Sona

I have 2 integer columns and want to sum up the commission with same trackId and insert it into another column of same table.But with Sum()function, I don't get as many number of sums as the number of rows in the table. My hard coded query looks like: UPDATE Temp_GetPercentage SET relPercentage = (SELECT sum(per.intImpressions) FROM Temp_GetPercentage as per WHERE track_id = 20) This should update all records with track_id = 20 and set relPercentage = (sum of intImpressions having track_id = 20)