Scaling Writes easy
In a standard Primary-Replica (Master-Slave) database architecture, to which node must the application send `INSERT` statements?
- A The Primary (Master) node only.
- B Any node (Round Robin).
- C The Replica nodes only.
- D The node with the least CPU usage.
Answer: A. The Primary (Master) node only.
To maintain data consistency, writes typically go to a single source of truth (Primary). Replicas are read-only copies used to scale Read traffic.
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