[raveworx]

I'm thinking about the same thing too. I haven't done it myself, but here are a few of the tables that I think need to be updated if the userids change. I may have missed a couple. Here are my rough thoughts on the process.

Delete old accounts
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Table: xcart_customers

Delete any old duplicate accounts (or if you want to keep them around for archive purposes, put a counter on their e-mail address...i.e. fake@address.com_1,fake@address.com_2 so they're no longer duplicate)


Relink records to newest account
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xcart_orders

This action would move any previous orders into the new account, so that the full order history is maintained.


Delete records pointing to any old accounts
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xcart_newslist_subscription
xcart_change_password
xcart_old_passwords
xcart_address_book
xcart_stats_customers_products

You don't want duplicate primary address records, for example, so just throw away the records in these tables that are linked to the old user ids.