ADOdb
From MoodleDocs
For more information about adodb, you could go to http://adodb.sourceforge.net/
The whole idea behind adodb is that PHP's database access functions are not standardized. This creates a need for a database class library to hide the differences between the different database API's (encapsulate the differences) so we can easily switch databases.
Adodb currently support MySQL, Oracle, Microsoft SQL Server, Sybase, Sybase SQL Anywhere, DB2, Informix, PostgreSQL, FrontBase, Interbase (Firebird and Borland variants), Foxpro, Access, ADO, SAP DB, SQLite and ODBC. We have had successful reports of connecting to Progress and other databases via ODBC.
