title: How i can count item in one column with SQL statement
body: <p>I have one DB (programming is with Delphi) , and I want to count an item in one column.</p>
  
  <p>For example, the table like this:</p>
  
  <pre><code>column1    | column2
  -----------+-------------
  employee1  | employee2
  employee3  | employee1
  employee1  | employee1
  employee2  | employee3
  </code></pre>
  
  <p>I want to count employees in that columns, for example, how i can get result <code>2</code>, from <code>count( employee1)</code> in <code>column1</code>?</p>