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