PostgreSQL (SQL) Versus DynamoDB (Key-Value NoSQL)
TradeoffMidSeniorUpdated
You're building a banking ledger with multi-row transactions and complex reports across accounts, transactions, and customers.
Short answer: PostgreSQL (SQL). Multi-row atomicity, consistency, isolation, durability (ACID) transactions + ad-hoc joins/reports are exactly what relational engines exist for.
The Two Options
A
PostgreSQL (SQL)
B
DynamoDB (Key-Value NoSQL)
Drill This: Your Pick First
The Better Pick
Option A
PostgreSQL (SQL)
Multi-row atomicity, consistency, isolation, durability (ACID) transactions + ad-hoc joins/reports are exactly what relational engines exist for. NoSQL forces app-side joins and either denormalization or distributed transactions.
When the Other One Wins
DynamoDB (Key-Value NoSQL)
If access patterns were a small fixed set keyed by account_id and you needed extreme write throughput, DynamoDB-style design would win.