---

SELECT DISTINCT
    t2.table_name,
    t2.column_name
FROM information_schema.columns t2
WHERE t2.table_schema = 'back_office'
  AND t2.column_name = 'contract_id'
  AND t2.table_name IN (
    SELECT table_name 
    FROM information_schema.columns
    WHERE table_schema = 'back_office'
      AND column_name = 'operation_id'
  )
ORDER BY t2.table_name