PostgreSQL is one of the largest and mature open source projects today. The project maintains over a dozen mailing lists, as well as several user groups, an active IRC community, and international sites in multiple languages. The active community has not only produced an outstanding database, but is also known for having some of the best open source documentation available today.
Full list of features:
| Feature | PostgreSQL |
| Primary Differentiators(s) | Professional Click-Through Binary Installer |
| Supported Platforms | Linux x86/32 Linux x86/64 Windows® Mac OS® X |
| Full ACID compliance | |
| Views / User Defined Data Types | |
| ANSI Constraints | |
| Functional Indexes | |
| Partial Indexes | |
| Data and Index Partitioning | |
| Bitmap Indexes | |
| Primary and Foreign keys | |
| Rules Engine | |
| Inheritance | |
| Triggers & Stored Functions | |
| Nested Transactions | |
| Procedural Language support | |
| SQL/XML Support | |
| Multi-version Concurrency Control (MVCC) | |
| Full Text Search | |
| PostgreSQL Database Links | |
| Pluggable Authentication | |
| Heap-Only Tuples (HOT) | |
| Online Reorganization | |
| Online Backup | |
| Interactive SQL Termina | |
| Client Connectors | libpq |
| Asynchronous Pre-Fetch for RAID | Bitmap Indices |
| Programming Language Support | PL/pgSQL PL/Java® PL/Ruby PL/Python PL/PHP PL/Perl C/C++ PL/Tcl PL/Scheme |
| Library Interface Support | libpq JDBC ODBC .NET™ Perl Python Ruby C/C++ PHP Lisp Scheme Qt |