Hello all.
I have two customer tables in different servers (A and B). They contain many common custumers, but the Id's are different, so my client provided me with a table with the id equivalence of the common customers (ie, customer 5 in table A is customer 3 in table B and so on). If the customer in B has no equivalent in A then the equivalent ID is blank.
My client wants to generate a single customers table with the same customer id in both databases. It seems easy but there are problems:
What happens if customer 3 in A is customer 5 in B and customer 7 in A is customer 3 in B? If I change the Ids that equivalence never happens.

So here I am asking for ideas.
Regards