title: SQL count certain values in multiple columns
body: <p>I have a table with with 3 possible values (1,0,NA)</p>
  
  <pre><code>Customers | Answer1 | Answer2 | Answer3
  -----------------------------------
  John      |   1     |  0     |  NA 
  Dave      |   NA    |  0     |  NA      
  Jane      |   0     |  1     |  1
  Tom       |   1     |  0     |  0
  </code></pre>
  
  <p>I am trying to count only the 1 and 0 as values. </p>
  
  <p>The result of query that I am trying to achieve is: </p>
  
  <pre><code>Customers | Total_Score
  -----------------------
  John      |    2
  Dave      |    1
  Jane      |    3
  Tom       |    3
  </code></pre>
  
  <p>Using MySQL for a database. </p>
  
  <p>I tried using:
  <code>SELECT Customers, COUNT(Answer1 + Answer2 + Answer3) AS Total_Score FROM exam</code>. The SQL query only summed the values, not count the values 1 and 0. Thanks for all your help. I have been stuck and been searching, but no luck. </p>