title: Counting info in mysql
body: <p>i have a problem, am trying to count all notice's for people i have in same row table friends</p>
  <p>its like counting all notice which you must see</p>
  <p>but am getting this error</p>
  <p>:mysql::st execute failed: Operand should contain 1 column(s)</p>
  <pre><code>TABLE  notice
  
  id  user  info
  1   0771  tes
  2   0881  coma
  3   0555  tue
  
  TABLE friends
  
  id  acc    friend
  1   0771   0881
  2   0881   0555
  3
  </code></pre>
  <p>QUERY</p>
  <pre><code>SELECT count(*) 
  FROM notice 
  WHERE user IN (SELECT acc, friend 
                 FROM friends 
                 WHERE acc = '0771' 
                    OR friend = '0771')
  </code></pre>