InstantForum.NET v4.1.4Teradata Forumshttp://www.teradata.com/teradataforum/info@teradata.comWed, 03 Dec 2008 21:30:36 GMT20http://www.teradata.com/teradataforum/Topic11381-1-1.aspxHi Rahul,ISNULL is proprietary, replace it with COALESCE, which is also supported by MS SQL Server. There are some minor differences, but you don't have to care about it in that case:COALESCE(ACC_DET.user_name,' ') as usrCOALESCE(MAX(COALESCE(ACCESS_DATE,'')),' ') as max_access Is access_date really a string and not a datetime?DATEDIFF might be replaced by Standard SQL interval calculation, if it's in DAYs then it's even easier:access_date > (select max(access_date) from cess_details ) - 90DieterFri, 09 May 2008 07:22:59 GMTdnoethhttp://www.teradata.com/teradataforum/Topic11381-1-1.aspxHi,If anyone can help me in conversion of query to teradata1.isnull(ACC_DET.user_name,' ') as usr2. isnull(MAX(isnull(ACCESS_DATE,'')),' ') as max_access 3.datediff(day, access_date , (select max(access_date) from cess_details )) < 90Thu, 08 May 2008 04:45:28 GMTRahulG