Handboekje

PostgreSQL

PostgreSQL is a general purpose and object-relational database management system, the most advanced open source database system. PostgreSQL was developed based on POSTGRES 4.2 at Berkeley Computer Science Department, University of California.

Temporal Tables Extension (github)

https://github.com/arkhipov/temporal_tables
A temporal table is a table that records the period of time when a row is valid. There are two types of periods: the application period (also known as valid-time or business-time) and the system period (also known as transaction-time).
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PostgreSQL 10.13 Documentation

https://www.postgresql.org/docs/10/index.html
The PostgreSQL Global Development Group
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What is PostgreSQL?

https://www.postgresqltutorial.com/what-is-postgresql/
PostgreSQL is free and open source software. Its source code is available under PostgreSQL license, a liberal open source license. You are free to use, modify and distribute PostgreSQL in any form.
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