independent implementation of both the ODBC and X/Open specifications. 

Information about this library can be found at: 

http://www.iodbc.org

unixODBC

unixODBC (

http://www.unixodbc.org

) is an open source project whose 

goals are to develop and promote unixODBC to be the definitive standard for 

ODBC on the Linux platform. 

Unified ODBC

Unified ODBC consists of a single set of ODBC functions provided by PHP to 

access different databases that have borrowed the semantics of ODBC API 

to implement their own API. It is more efficient to use the database native 

database driver because there is no ODBC involved in the communication or 

access path.

ADOdb

ADOdb library provides a wrapper around MySQL API for supporting MySQL 

database, and wrapper around DB2 ODBC Driver for DB2 UDB. So you need 

the Unified ODBC support for using ADOdb libraries.

PEAR

PEAR DB is the default database abstraction library included in PHP4, and it 

is quite similar to the more popular ADOdb library. As PEAR DB is also a 

wrapper around the DB2 ODBC driver, the Unified ODBC DB2 support must 

be provided for using PEAR DB libraries.

When we talk about ODBC in this section (always Unified ODBC), respectively 

the native DB2 driver is meant. Because of the wide similarities in the syntax 

between Unified ODBC and other ODBC types, and the performance advantage 

when using the Unified ODBC support, the application conversion is discussed 

with the Unified ODBC support.

Converting from native MySQL library to Unified ODBC

Using the Unified ODBC support in PHP applications does not require a special 

load of library files as the support already is integrated during the compilation 

process of PHP. A complete overview about the MySQL and the Unified ODBC 

functions can be found in the 

PHP Manual,

 which can be downloaded at: 

http://www.php.net/docs.php

Connecting database

Connecting a MySQL database consists of two parts: First a connection to the 

MySQL server has to be established and after that a database can be chosen. 

The function specified to connect the MySQL server is given in the following 

declaration:

178 

MySQL to DB2 UDB Conversion Guide