title: How to select records without duplicate on just one field in SQL?
body: <p>I have a table with 3 columns like this:  </p>
  
  <pre><code>+------------+---------------+-------+  
  | Country_id | country_title | State |  
  +------------+---------------+-------+    
  </code></pre>
  
  <p>There are many records in this table. Some of them have <code>state</code> and some other don't. Now, imagine these records:  </p>
  
  <pre><code>1 | Canada  | Alberta  
  2 |  Canada | British  Columbia  
  3 | Canada  | Manitoba  
  4 | China   |
  </code></pre>
  
  <p>I need to have country names without any duplicate. Actually I need their <code>id</code> and <code>title</code>, What is the best SQL command to make this? I used <code>DISTINCT</code> in the form below but I could not achieve an appropriate result.  </p>
  
  <pre><code>SELECT DISTINCT title,id FROM tbl_countries ORDER BY title
  </code></pre>
  
  <p>My desired result is something like this:  </p>
  
  <pre><code>1, Canada  
  4, China
  </code></pre>