Recursive CTE — Chargeback Chain Investigation

Chargeback chains map fraud rings. When a customer disputes a transaction, the chargeback team traces related disputes — same merchant, same account, prior disputes that triggered this one. Use a WITH RECURSIVE CTE to walk the dispute chain starting from chargeback_id = 1, following related_chargeback_id edges (downstream chargebacks that reference this one as their root).

The anchor is the seed (chargeback 1). The recursive step joins to the CTE itself, finding chargebacks whose related_chargeback_id matches a chargeback already in the chain. Limit depth < 5 to prevent runaway recursion if the data has cycles.

Show chargeback_id, txn_id, account_id, depth. Order by depth ascending, then chargeback_id ascending.