PHP Connect to the MySQL Server

Use the PHP mysqli_connect() function to open a new connection to the MySQL server.

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Open a Connection to the MySQL Server

Before we can access data in a database, we must open a connection to the MySQL server.

In PHP, this is done with the mysqli_connect() function.

Syntax

mysqli_connect(host,username,password,dbname);

Parameter	Description
host	Optional. Either a host name or an IP address
username	Optional. The MySQL user name
password	Optional. The password to log in with
dbname	Optional. The default database to be used when performing queries

Note: There are more available parameters, but the ones listed above are the most important.

In the following example we store the connection in a variable ($con) for later use in the script:

<?php
// Create connection
$con=mysqli_connect("example.com","peter","abc123","my_db");

// Check connection
if (mysqli_connect_errno()) {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
?>

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Close a Connection

The connection will be closed automatically when the script ends. To close the connection before, use the mysqli_close() function:

<?php
$con=mysqli_connect("example.com","peter","abc123","my_db");

// Check connection
if (mysqli_connect_errno()) {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

mysqli_close($con);
?>