Reading path · 5 stops · 20 min of reading · 3 tools and data pages
IDs and timestamps that sort.
What you'll learnWhy UUIDv7 beats v4 as a database key, which libraries keep order, and tools to make and decode IDs and times.
The path, in order
Topics: App development, Rust. Ticks show what you have read in this browser.
- Explainer · 7 minUUIDv7 vs UUIDv4: which should you use?
Use UUIDv7 for database primary keys and anything you sort or index by ID: it starts with a millisecond timestamp, so new IDs always land at the end of the index instead of at random spots. In our test on a...
- Article · 13 minPick a UUIDv7 library that keeps order: 10 tested, .NET fails 50%
We tested 10 UUIDv7 libraries with 1M IDs each and a clock jump. .NET put 50% out of order, uuid6 ran 16.6 min ahead. The 2 that passed, plus free data.
- Free toolUUID v7 generator
Time-ordered UUIDs (RFC 9562), and the timestamp read back out of any v7, v6 or v1.
- Free toolSnowflake ID decoder
Discord or X (Twitter) ID to the exact millisecond it was made, and back.
- Free toolUnix timestamp converter
Timestamp to date in any time zone and back, plus all 9 Discord timestamp codes.
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