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Update bit mapping in README.md #18

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Update bit mapping in README.md #18

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4 changes: 2 additions & 2 deletions README.md
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Original file line number Diff line number Diff line change
Expand Up @@ -7,8 +7,8 @@ Internally, `snowflakes` are 64 bit integers represented externally as `bigint`
```
bit 63 - unused (sign of int8)
bits 22-62 - timestamp with millisecond precision
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@ashwinstar ashwinstar Apr 25, 2025 •
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(no specific to this PR) I am curious to learn on the design choice -

  • why timestamp was introduced? ideally node-id + counter should give unique sequence values to each node as well
  • If timestamp with millisecond precision is used then why is there a need to WAL log the updates to this sequence type?

bits 10-21 - counter within one millisecond
bits 0-9 - unique PostgreSQL node number set in postgresql.conf
bits 12-21 - counter within one millisecond
bits 0-11 - unique PostgreSQL node number set in postgresql.conf
```

* The timestamp is a 41-bit unsigned value representing millisecond
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