title: How to eliminate duplicates from select query?
body: <p>Before asking this question I searched using Google but I couldn't understand or maybe could not find a solution suitable for my situation.</p>
  
  <p>So, I have one Table with 10 columns, I want to eliminate duplicates from <strong>select</strong> result. And in the result all columns should be presented which has unique userID's</p>
  
  <pre>
  +-----------------------------------+------+---------------------+------+
  | name                              | yr   |   some Columns      |userID|
  +-----------------------------------+------+---------------------+------+
  | abc                               | 2000 |                     |   10 |
  | jack                              | 2000 |                     |   11 |
  | dadas                             | 2000 |                     |   12 |
  | jack                              | 2004 | .............       |   11 |
  | jack                              | 2000 | ...........         |   11 |
  | nell                              | 2006 | .............       |   13 |
  | ......                            | 2000 | .............       |   1  |
  | .............                     | 2000 | .............       |   2  |
  | again                             | 2000 | .............       |   3  |
  | again                             | 2000 |                     |   3  |
  | .......                           | 1973 | .............       |   2  |
  | abc                               | 2000 |                     |   10 |
  </pre>