Numbers To Know easy
What is the standard raw binary size of a Universally Unique Identifier (UUID)?
- A 8 Bytes
- B 32 Bytes
- C 64 Bytes
- D 16 Bytes
Answer: D. 16 Bytes
A UUID (Universally Unique Identifier) is a 128-bit value, which takes up exactly 16 Bytes of raw memory ($128 / 8 = 16$). However, you will often see UUIDs represented as hex strings, like `550e8400-e29b-41d4-a716-446655440000`, which consume 36 bytes of storage. Choosing to store UUIDs as raw binary instead of strings is a simple but effective optimization that can save significant storage space and improve indexing performance in large-scale databases.
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