[PHP] question about using sql server with php

[Sudhakar]

i have a question about how to use sql database with php instead of using my
sql database

when i use my sql database the php code to connect to the my sql database is
=

$conn = mysql_connect($hostname, $user, $password);

if(!$conn)
{
echo "Unable to connect to Database";
}

else
{
mysql_select_db($database, $conn);

$query = mysql_query($selectquery);

mysql_close($conn);
}


if i have to connect to a sql databse instead of my sql database as some
companies use sql database, how can i change the php code to connect, run a
query and close connection to the sql database.

apart from changing the code to connect to sql database is there something
else i need to do.

please advice.

thanks