http://sqlrelay.sourceforge.net/

SQL Relay is a persistent database connection pooling, proxying and load balancing system for Unix and Linux.

SQL Relay is ideal for:

• speeding up database-driven web-based applications
• enhancing the scalability of database-driven web-based applications
• distributing access to replicated databases
• throttling database access
• accessing databases from unsupported platforms
• migrating applications from one database to another

SQL Relay supports the following database backends:

• Oracle
• MySQL
• mSQL
• PostgreSQL

• Sybase
• MS SQL Server
• IBM DB2
• Interbase

• Sybase
• SQLite
• Lago
• ODBC

The SQL Relay client API''''s support advanced database operations such as bind variables, multi-row fetches, client side result set caching and suspended transactions. SQL Relay is has native client API''''s for the following languages:

• C
• C++
• Perl

• Python
• PHP
• Ruby

• Java
• TCL
• Zope

SQL Relay provides drivers for the following database abstraction layers:

• Perl DBD

• Python DB

• Ruby DBD

• PHP Pear DB

An application coded using another database''''s native client API may be able to use SQL Relay without modification. SQL Relay provides drop-in replacement libraries for:

• MySQL

• PostgreSQL

SQL Relay also features:

• command line clients
• a GUI configuration tool
• extensive documentation