70 lines
2.0 KiB
Markdown
70 lines
2.0 KiB
Markdown
UUID Note
|
|
|
|
|
|
1.github - uuidv7: A JavaScript implementation of UUID version 7
|
|
|
|
https://github.com/LiosK/uuidv7
|
|
https://unpkg.com/uuidv7@1.0.2/dist/index.js
|
|
|
|
2.sql function: Implementing V7 UUID in Postgres - How to implement v7 UUID in postgres with using SQL
|
|
|
|
https://priver.dev/blog/postgres/implementing-v7-uuid-in-postgres/#:~:text=We%20use%20clock_timestamp%20to%20obtain%20the%20current%20time%2C,millisecond%20timestamp%20to%20a%20byte%20sequence%20using%20int8send.
|
|
|
|
``` sql
|
|
CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
|
|
|
|
create or replace function uuid_generate_v7()
|
|
returns uuid
|
|
as $$
|
|
select encode(
|
|
set_bit(
|
|
set_bit(
|
|
overlay(uuid_send(gen_random_uuid())
|
|
placing substring(int8send(floor(extract(epoch from clock_timestamp()) * 1000)::bigint) from 3)
|
|
from 1 for 6
|
|
),
|
|
52, 1
|
|
),
|
|
53, 1
|
|
),
|
|
'hex')::uuid;
|
|
$$
|
|
language SQL
|
|
volatile;
|
|
```
|
|
|
|
3.Extract Timestamp from UUID v7 using Javascript
|
|
|
|
https://park.is/blog_posts/20240803_extracting_timestamp_from_uuid_v7/
|
|
|
|
// extract Unix timestamp from a UUID v7 value without an external library
|
|
|
|
在没有外部库的情况下从 UUID v7 值中提取 Unix 时间戳
|
|
|
|
``` javascript
|
|
function extractTimestampFromUUIDv7(uuid: string): Date {
|
|
// split the UUID into its components
|
|
const parts = uuid.split("-");
|
|
|
|
// the second part of the UUID contains the high bits of the timestamp (48 bits in total)
|
|
const highBitsHex = parts[0] + parts[1].slice(0, 4);
|
|
|
|
// convert the high bits from hex to decimal
|
|
// the UUID v7 timestamp is the number of milliseconds since Unix epoch (January 1, 1970)
|
|
const timestampInMilliseconds = parseInt(highBitsHex, 16);
|
|
|
|
// convert the timestamp to a Date object
|
|
const date = new Date(timestampInMilliseconds);
|
|
|
|
return date;
|
|
}
|
|
|
|
// sample usage:
|
|
const uuid = "01911825-7f8f-74c9-85bc-55b034e2af75";
|
|
const timestamp = extractTimestampFromUUIDv7(uuid);
|
|
|
|
// check output
|
|
console.log(timestamp);
|
|
// prints "Sat Aug 03 2024 07:09:56 GMT-0500 (Central Daylight Time)"
|
|
|
|
``` |