If you're not distributed, use an incrementing integer. If you're distributed, look into vector clocks[1] or snowflake[2][3] [1] https://en.wikipedia.org/wiki

If you're not distributed, use an incrementing integer. If you're distributed, look into vector clocks[1] or snowflake[2][3] [1] https://en.wikipedia.org/wiki/Vector_clock https://en.wikipedia.org/wiki/Vector_clock [2] https://github.com/twitter-archive/snowflake/tree/snowflake-2010 https://github.com/twitter-archive/snowflake/tree/snowflake-... [3] https://en.wikipedia.org/wiki/Snowflake_ID https://en.wikipedia.org/wiki/Snowflake_ID