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Finally, an open source SQL database with history for data builtin: https://mariadb.com/kb/en/library/system-versioned-tables/

Always wondered why this feature has been ignored for so long.

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Thanks for pointing that out! They appear to only support one of the two time models proposed by the research community. They support transaction time (when you write it), but not the interesting and useful 'valid time'. The difference can be explained as you are going to be paid a salary for working say from July 1, 2018 to June 30, 2019 (this is valid time), but we write the information into the db at a different time, say we write it on June 15 (this is transaction time), then we realize a mistake and update your salary record on June 20th. But your employment starts July 1.

Just FYI: The SQL standard supports both types. The other one (valid time) is called "application versioning" in SQL.

Read this paper if you'd like to learn more about it: http://cs.ulb.ac.be/public/_media/teaching/infoh415/tempfeat...

Cool I hadn't heard about that.

Hum, you don't have the syntaxic sugar but I'm pretty sure you can do bitemporal tables for sometimes in PostgreSQL.

No features come for free. How do you justify the universal value of this feature?

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