title: Drop a foreign key from a table in mysql
body: <p>I have created a foreign key without giving it a name for a column in a table. Now i want to remove that column. First i've tried removing the foreign key constraint but there was an error <br>
  I've used the following sql command <br></p>
  
  <pre><code>ALTER TABLE passenger 
  DROP FOREIGN KEY bookedBy
  </code></pre>
  
  <p>The error message</p>
  
  <blockquote>
    <p>#1091 - Can't DROP 'bookedBy'; check that column/key exists <br></p>
  </blockquote>
  
  <p>i've ensured that the column exist.<br>
  I have not named the foreign key constraint. Is it possible to remove the foreign key constraint without naming it. Is there any default naming given to the foreign keys.</p>