title: How to DROP PRIMARY KEY from Column in SQL Server 2008 R2
body: <p>I have a one more question about T-SQL</p>
  
  <p>I´d like to DROP a PRIMARY KEY in database <code>[COST_mesta_test].[dbo].['1965$']</code> ,table <code>'1965$'</code></p>
  
  <p>I have primary key on column <code>obec</code> (it´s <code>varchar</code> column) and this doesn´t work</p>
  
  <pre><code>ALTER TABLE [COST_mesta_test].[dbo].['1965$'] 
  DROP CONSTRAINT obec
  </code></pre>
  
  <p>It´s give me an error </p>
  
  <blockquote>
    <p>'obec' is not a constraint. Msg 3727, Level 16, State 0, Line 1 Could
    not drop constraint. See previous errors.</p>
  </blockquote>
  
  <p>Really don´t know why, because 'obec' is really PK.</p>
  
  <p>Thanks a lot for help!</p>