how to connect to another database in wordpress

Question

I am trying to connect with another database in WordPress and insert data into a new table. I am creating a new object of wpdb

$newconnection= new wpdb("localhost","username","password","databasename");

and then trying to insert the data:

$newdb->insert('tablename', array('fullname'=> $_REQUEST['fullname'],'email'=> $_REQUEST['email']);

but i am not able to insert the data into new table of the new database.

its showing the error "ERROR ESTABLISHING A DATABASE CONNECTION".

Please try to resolve my query

Answer 1

Look at the order of the constructor arguments in the documentation:

string $dbuser, string $dbpassword, string $dbname, string $dbhost

You've got the arguments in the wrong order. Move the host to the end:

$newconnection= new wpdb("username","password","databasename","localhost");