handling SQL dot notation in PHP

When using SQL in PHP I have run up against a small issue when working with larger SQL queries...specifically when using alias table names. PHP doesn't like the "." used to seperate the table/field name. Here is an example: $query = "SELECT Role.display_Name from Northwind"; This generates an error because of the "." symbol in the query. This is a very rudimentary query used simply for ease of understanding of the problem...but on a larger query where it is necessary to denote field/table relationships using the period becomes crucial. How can I get around PHP's issue with the "."? Thanks, ROn