DB is a database abstraction layer providing:
* an OO-style query API
* portability features that make programs written for one DBMS work with other DBMS's
* a DSN (data source name) format for specifying database servers
* prepare/execute (bind) emulation for databases that don't support it natively
* a result object for each query response
* portable error codes
* sequence emulation
* sequential and non-sequential row fetching as well as bulk fetching
* formats fetched rows as associative arrays, ordered arrays or objects
* row limit support
* transactions support
* table information interface
* DocBook and phpDocumentor API documentation

DB layers itself on top of PHP's existing database extensions.

Drivers for the following extensions pass the complete test suite and provide
interchangeability when all of DB's portability options are enabled:

fbsql, ibase, informix, msql, mssql,
mysql, mysqli, oci8, odbc, pgsql,
sqlite and sybase.

There is also a driver for the dbase extension, but it can't be used
interchangeably because dbase doesn't support many standard DBMS features.

DB is compatible with both PHP 4 and PHP 5.