Switch UUID generation from v4 to v7#18
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Use SecureRandom.uuid_v7 (Ruby 3.4+) instead of SecureRandom.uuid (v4). UUIDv7 (RFC 9562) embeds a 48-bit unix timestamp, so primary keys naturally sort chronologically. This fixes comment reply ordering and improves B-tree index locality. Amp-Thread-ID: https://ampcode.com/threads/T-019c9157-b075-7443-9d10-f4aa772fec8f Co-authored-by: Amp <amp@ampcode.com>
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What
Switches
ApplicationRecord#assign_uuidfromSecureRandom.uuid(v4, random) toSecureRandom.uuid_v7(Ruby 3.4+, time-ordered).Why
UUID v4 primary keys sort in random order, which caused comment replies to appear out of order. UUIDv7 embeds a 48-bit millisecond timestamp in the high bits, so PKs naturally sort chronologically.
Bonus: time-ordered UUIDs improve B-tree index locality, reducing page splits and improving query performance.
Notes
SecureRandom.uuid_v7.