swoveland21 (12/6/2010)
Account table has 121,000 records and call has 651,000 records. Due to account type clause there are only 8,000 acount and 98,000 call records affected. I wonder why the results are so different, acctid is primary key and index does exist on callactid.
Without seeing the plan its hard to say for definite , but as you require a large portion of the data (651K / 121 K = 20% roughly assuming that each account has 1 call ) , then the single scan through the call table is more efficient that the seeks to find the first call. In my example we were required to find a tiny portion on the data 1mill / 100 = 0.01% .