Idempotency Situation

Ensuring Reliable Money Transfers Using Database Transactions In a digital wallet system similar to PhonePe, Google Pay, or Paytm, users expect their money to be handled accurately and securely. Even a small inconsistency—such as deducting money from one account without crediting another—can lead to serious financial issues. To prevent such problems, database systems rely on ACID properties, especially Durability, to guarantee safe and consistent transactions. System Overview The system maintains an accounts table where each user has a balance. Users can: Store money in their wallet Transfer money to other users View their transaction history To ensure correctness, the database enforces rules like non-negative balances and timestamp tracking. Performing a Secure Transfer A typical money transfer between two users (for example, Alice to Bob) is executed within a transaction: The system begins a transaction Deducts money from the sender’s account Adds the same amount to the receiver’s ac