>So i have tested your code i was run but doesn't replaced the ID such as 401 with 401R ..


Why not? What happens?

I've just written this down without testing. But mainly it should work that way.

Is it creating the record-copies?
What is the ID like. Maybe You need to replace the ID after inserting
if You have an insert trigger

However if this field is the primary key, this can be very dangerous anyway,
because making a copy from the same record twice will create an already
existing STOCKID.

HTH