It takes 14 minutes to execute this statement right after I start the SQL Server: update table1 set column2 = table2.column2 from table1, table2 where table1.crefid = table2.cid If I execute the same statement again right away, it only takes 25 seconds. If I restart the SQL Server and run the same statement, it will take 14 minutes the 1st time and then only 25 seconds. How can I find out why the 1st time takes 14 minutes and then it only takes 25 seconds? I guess this is something related to cache but I don't know how to check this. Thank you for any help.