mysqli_real_escape_string() expects exactly 2 parameters, 1 given

Documentation says it needs two parameters:

string mysqli_real_escape_string ( mysqli $link , string $escapestr )

The first one is a link for a mysqli instance, the second one is the string to escape.

Following is the proper format to use it :

string mysqli_real_escape_string ( mysqli $link , string $escapestr )

first parameter is mysql connection link identifier, and second is string For more details, you can visit this link : http://in2.php.net/manual/en/mysqli.real-escape-string.php.

Let me just add an extra bit of information: If you are using NetBeans, its documentation actually shows the mysqli_real_escape_string function like this:

mysqli_real_escape_string (PHP 5)
    Escapes special characters in a string for use in an SQL statement, taking into account the current charset of the connection

Parameters:

    string $escapestr
        'The string to be escaped.'

Returns:

    Type:
    string

Description:
    an escaped string.

This is wrong, though, as shown in the other answers. It requires both the $link and the $string.