title: can use more than 1 column in MySQL Group BY?
body: <p>I want to write these SQL Query:</p>
  
  <pre><code>CREATE VIEW `uniaverage` AS 
    SELECT `averagegrade`.`mjr`,`averagegrade`.`lev`, 
       AVG(`averagegrade`.`average`) AS `uniAVG` 
    FROM `averagegrade` GROUP BY `averagegrade`.`lev`, `averagegrade`.`mjr`;
  </code></pre>
  
  <p>But MySQL Query Browser gives me this error:</p>
  
  <pre><code>Operand Should Contain 1 column(s)
  </code></pre>
  
  <p>I somewhere read that I can use group by on more than 1 column!!!
  How can I solve this error? or how can I change the Query to get the same result? </p>