Customer Merge

Customer Merge

Customer Merge finds duplicates by email, phone, name and address, showing an exact preview before anything is written and keeping a one-click undo. It scans your customer base and tells you which accounts are duplicates, scoring pairs based on independent evidence such as the same email, Gmail alias, phone number, name at the same postcode, company or VAT number, and matching guest checkout to registered account. Signals of the same kind do not stack and contradicting evidence subtracts, reflecting actual certainty.

Dry Run

A dry run before anything is written shows the exact plan: which tables are touched, which strategy applies to each, and how many rows will move, be deduplicated or stay untouched. Your invoices stay exactly as they were issued; only the owner of an order changes. Invoices, credit slips, payments, order details, carriers, order history and stock movements are never rewritten. An address that an order points at keeps its ID and every field that appears on your documents, even when an identical duplicate of it is collapsed.

Known Modules

The module knows about the modules you installed and discovers every table carrying a customer reference, including ones it has never seen. Each one is listed with its row count, its risk on repointing, and a strategy you choose: move the rows, move and collapse exact duplicates, leave the table alone, or ask every time. A table it cannot roll back, one with a trigger, a view, or a table without a primary key blocks the merge rather than being merged on a best-effort basis. One click puts it back.

Undo

A merge writes an encrypted snapshot of every row it changed, so undo is a button rather than a restore from backup. Undo refuses when it would overwrite something that changed after the merge, when an absorbed customer ID has been reused, or when an erasure request removed the snapshot. Customer sessions are the deliberate exception: they are revoked by the merge and never restored, because handing back a live login would be an account takeover path.

Audit Trail

An audit trail that shows its own tampering appends each merge, undo and failure to a hash-chained log: each entry includes the hash of the one before it, so a removed or edited entry breaks the chain visibly. The log holds what happened and who did it, never customer data. It exports to CSV for whoever asks.