title: What is the syntax of string concatenation in PHP while writing a sql query
body: <p>How do I concatenate a string with a PHP variable in a SQL query?</p>
  
  <p>Example:</p>
  
  <pre><code>select User from users where id="badge_name""$user_id"
  </code></pre>
  
  <p>Please write a code example of concatenation for <code>badge_name</code> and <code>user_id</code> string.
  Actually I forgot how I did this last time
  It was like ."hello". With some other string. Please be more specific...
  Thanks</p>