UUID vs. Auto-Increment: A Developer's Dilemma

The Classic: Auto-Increment

For decades, databases used simple integers (ID 1, ID 2). It's fast and easy to read. But it leaks information. If I sign up and get User ID 500, I know you only have 500 users.

The Modern: UUID (Universally Unique Identifier)

A UUID looks like this: 123e4567-e89b-12d3.... It is 128-bit and effectively unique across the entire universe.

Why Use UUIDs?

• Security: Impossible to guess the next ID.
• Distributed Systems: You can generate IDs on the client-side without asking the central database (great for offline apps).
• Merges: Merging two databases is easy because IDs won't conflict.

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