Thanks for all the suggestions.

For Piotr's solution, I have never written JOIN like you suggested. It would be worth testing and see if it works in my case.

For Garadin's...

Thank you for your reply. My task is that I have a master data (says TableA) with 4x,xxx records. Users need to map sets of data into groups...

I reply not because I know the solution but I want to share that I got the same problem with MySQL linked server (through ODBC). It seems that the...