My update looks like this. I have a clustered index on adid on the txtad table, so I thought this would affect only a single row. Instead it takes a while to come back and gives the message below..
update txtad set filelocation ='http://image.homedepotemail.com/lib/fe6b1570746006757114/m/10/THDC157_2.01.jpg'
where adid =80563
(10626 row(s) affected)
(10626 row(s) affected)
(1 row(s) affected)
Why is this update affecting 10626 rows?