title: MyISAM locks on large select statements
body: <p>On a MyISAM engine MySQL server (5.1)</p>
  
  <p>We have some large query to make a report (1 million results). I notice that these select statements lock the tables. 
  I don't find a real explanation for this on the internet. From what I understand the tables should only lock when switching between select and insert (etc) statements.</p>
  
  <p>I found someone with the same problem <a href="http://devoluk.com/mysql-myisam-table-lock-issue.html" rel="nofollow">http://devoluk.com/mysql-myisam-table-lock-issue.html</a></p>
  
  <p>When i convert the tables to innodb the table locks don't happen. Unfortunately converting in production takes days, so its not really an option.</p>
  
  <p>Did someone have the same issue, or how to make it non blocking?</p>