Postgresql

PostgreSQL is a relational database manager system based on postgres version 4,2, developed in the department of Computer Sciences in the University of California at Berkeley. Postgres was a pioneer in many concepts that appeared much later in some of the commercial database systems.

PostgreSQL is a open source descendant of the original code of Berkeley. It supports SQL92 and SQL99 in addition to other modern characteristics, among them:

• Complex queries
• Foreign keys.
• Triggers
• Views
• Transactional integrity.
• Concurrency control multi-version.

• Data types
• Functions
• Operators
• Aggregation functions.
• Procedure languages.