PHP mysqli_connect() Function

The mysqli_connect() function in PHP is used to connect you to the database. In the previous version of the connection, the mysql_connect() was used for connection and then there comes mysqli_connect() function where i denotes an improved version of the connection and is more secure than mysql_connect().

Syntax:

mysqli_connect ( "host", "username", "password", "database_name" );

Parameters Used:

• host: It is optional and it specifies the hostname or IP address. In the case of local server, localhost is used as a general keyword to connect the local server and run the program.
• username: It is optional and it specifies MySQL username. In the local server username is root.
• Password: It is optional and it specifies MySQL password.
• database_name: It is a database name where operations perform on data. It is also optional.

Return Value:

• It returns an object which represents the MySql connection. If the connection failed then it returns FALSE.

Program: Below is the implementation of mysqli_connect() function.

php

<?php
mysqli_connect("localhost", "root", "", "GFG");

if (mysqli_connect_error()) {
    echo "Connection Error.";
} else {
    echo "Database Connection Successfully.";
}
?>

Output:

Database Connection Successfully.

We can also use the die() method to terminate the program with a message if the connection fails.

Program: Below is the implementation of the die() method with the mysqli_connect() method.

PHP

<?php
mysqli_connect("localhost", "root", "", "GFG") or
    die("Connection Unsuccessfull");

// If the connection is successfull then
// the program does not terminates
// and the following message is displayed.
echo "Connection Successfull";
?>

Output:

Database Connection Successfully.