Download PostgreSQL 9.1

Version 9.1 of PostgreSQL has been released. This popular ‘open source relational database management system’ runs on a large number of operating systems and can therefore be used in various environments. It is a derivative of Ingres, after its lead developer started his own business and that open source database became closed source. An extensive list of changes is on this page to find. This is a brief overview of the main improvements:

Major enhancements include:

• allow synchronous replication
• Add support for foreign tables
• Add per column collation support
• Add extensions which simplify packaging of additions to PostgreSQL
• Add a true serializable isolation level
• Support unlogged tables using the UNLOGGED option in CREATE TABLE
• Allow data-modification commands (INSERT/UPDATE/DELETE) in WITH clauses
• Add nearest-neighbor (order-by-operator) searching to GiST indexes
• Add a SECURITY LABEL command and support for SELinux permissions control
• Update the PL/Python server side language

PostgreSQL screenshot, click on the image for a larger version.