PostgreSQL (often Postgres) is a powerful, object-relational database system (ORDBMS, to be even more specific).
Open source since 1996, it has a proven architecture that has earned it a strong reputation for reliability, data integrity, and correctness. Standards compliance is a major focus of the development team. Postgres runs on all major operating systems, including Linux, UNIX (AIX, BSD, HP-UX, SGI IRIX, Mac OS X, Solaris, Tru64), and Windows.
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