Thanks Gail Shaw, MarcinGol and Vijay Mishra for replying and giving an insight of index performance to me.

Thanks a lot! Marcin for replying

(the table I projected here is just a sample table which is very much close to my real table)

Id is my Clustered Index as I'm...

Thanks for reply, yea looks like LEFT OUTER JOIN works better in this scenario.

Hello Atif Sheikh/Jack Corbett,

Thanks for the useful posts, it helped me a lot.

I'm doing the classic stuff in SQL Server update existing rows from Table1 to Table2 and Insert...