Managing & Using MySQL, 2nd Edition

The Connection

An application should call mysql_init( ) before performing any other operation. This method initializes a database handler used by many of the functions—including the connection and error handling functions. In the above example, we created a handler in the declaration:

MYSQL *connection, mysql;

The pointer to the handler, connection, will represent our actual connection once it is made; the allocated handler, mysql, represents a null connection until we actually make the database connection. Our first step is to initialize this handler through the mysql_init( ) function:

mysql_init(&mysql);

This function takes a reference to an allocated null handler. The MySQL API requires this hocus-pocus with a null handler to support operations such as error handling that occur outside the context of a physical database connection. The first function needing this handler is the actual connection API: mysql_real_connect( ).

Tip

At first glance over the API list, you may be tempted to use the mysql_connect( ) function. The odd name of the mysql_real_connect( ) function exists because it is a replacement for the long-deprecated mysql_connect( ) function. The old mysql_connect( ) provided compatibility for mSQL applications; you should never use it in modern applications.

The mysql_real_connect( ) function takes several arguments:

null handler

The connection handler allocated and subsequently initialized through mysql_init( ).

host

The name of the machine on which the MySQL server ...