Choosing a library

The mysqli, PDO_MySQL and mysql PHP extensions are lightweight wrappers on top of a C client library. The extensions can either use the mysqlnd library or the libmysqlclient library. Choosing a library is a compile time decision.

The mysqlnd library is part of the PHP distribution since 5.3.0. It offers features like lazy connections and query caching, features that are not available with libmysqlclient, so using the built-in mysqlnd library is highly recommended. See the mysqlnd documentation for additional details, and a listing of features and functionality that it offers.

// Recommended, compiles with mysqlnd
$ ./configure --with-mysqli=mysqlnd --with-pdo-mysql=mysqlnd --with-mysql=mysqlnd

// Alternatively recommended, compiles with mysqlnd as of PHP 5.4
$ ./configure --with-mysqli --with-pdo-mysql --with-mysql

// Not recommended, compiles with libmysqlclient
$ ./configure --with-mysqli=/path/to/mysql_config --with-pdo-mysql=/path/to/mysql_config --with-mysql=/path/to/mysql_config

Library feature comparison

It is recommended to use the mysqlnd library instead of the MySQL Client Server library (libmysqlclient). Both libraries are supported and constantly being improved.