In a previous guide, we discussed the high-level concepts of how databases manage multiple users—touching on transactions, locks, and connection pools. But if you're a backend engineer or preparing for a system design interview, you need to know what’s actually happening under the hood.
When 10,000 users hit a database simultaneously, how does the engine ensure data integrity without grinding to a halt? Let's dive deep into the architecture of database concurrency.
1. Concurrency Control Mechanisms
At the core of any relational database (like PostgreSQL or MySQL) is its Concurrency Control system. There are three primary strategies databases use to manage simultaneous access.
Pessimistic Concurrency Control (Locking)
