PostgreSQL is a very popular open-source database platform.

The homepage says: “PostgreSQL is a powerful, open source object-relational database system with over 35 years of active development that has earned it a strong reputation for reliability, feature robustness, and performance.”

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Alex the Analyst has a video where he compares MySQL, Microsoft SQL Server and PostgreSQL. The video is called MySQL vs Postgresql vs Microsoft SQL Server Management Tools | Which Option is Best? I haven’t used PostgreSQL yet (at the time of this writing) so i can’t compare the three. However, I’ve use SQL Server much more than MySQL and SQL Server is currently my favourite. Alex’s favourite is also SQL Server, however for beginners he recommends MySQL, partly because it is open source, just like PostgreSQL. One advantage of Microsoft SQL Server is that is has T-SQL built on top of the standard SQL language, which add a lot of powerful functionality to SQL.