title: Characters that SQL doesn't use
body: <p>I'm creating a php class that executes queries for me when I pass in a query and multiple parameters to use in the query. In the query string, instead of using $user,$password,etc, I would like to reference the additional parameters I pass in, such as </p>
  
  <pre><code>select * from info where user_id = &amp;param1
  </code></pre>
  
  <p>However, I do not want to use any character significant in a SQL statement for obvious reasons. What character should I go with to denote a query parameter in my query string?</p>