wordpress and database on different servers

I am building a wordpress site for a friend.
His server does not have msql but rather has mssql.

I thought the easiest thing would be to associate the wordpress site with a database on my server but i can not figure out if this will work and if so i am not sure what the entry in

>define(‘DB_HOST’, ”)

should look?
Any ideas?

Or is there a way to run WP off of a mssql database?

Thanks in advance guys.
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