title: SQL error: 'database.table.field isn't in GROUP BY
body: <p>I am getting this when I am installing a 3rd party software. I've read the related topics and all of them suggested to set <code>sql_mode</code> to an empty string (<code>SET sql_mode = ''</code>) but that solution didn't work for me. Still getting the same error. Do I need to set this in my config file or something?</p>
  
  <p>Here's some useful info;</p>
  
  <p><code>Server version: 5.6.15-56-log Percona Server (GPL), Release rel63.0, Revision 519</code></p>
  
  <pre><code>mysql&gt; SHOW VARIABLES LIKE 'sql_mode';
  +---------------+-------+
  | Variable_name | Value |
  +---------------+-------+
  | sql_mode      |       |
  +---------------+-------+
  1 row in set (0.00 sec)
  </code></pre>
  
  <p>And the failing query with error message is;</p>
  
  <pre><code>mySQL query error: SELECT MAX(e.entry_id) as max, MAX(e.entry_date) as maxdate,b.blog_id, b.blog_name, b.blog_seo_name FROM blog_entries e  LEFT JOIN blog_blogs b ON ( b.blog_id=e.blog_id )   WHERE e.entry_status='published' AND e.entry_banish=0 AND e.entry_featured=0 AND b.blog_view_level='public' AND b.blog_disabled=0 GROUP BY e.blog_id, b.blog_name, b.blog_seo_name ORDER BY maxdate DESC LIMIT 0,50
  
  SQL error: 'db_name_ipb.b.blog_id' isn't in GROUP BY
  SQL error code: 1055
  </code></pre>
  
  <p>Any idea ?</p>
  
  <h2>UPDATE</h2>
  
  <p>Unfortunately the codes are encrypted, so there is no way to try your suggestions. Also -as specified above- changing the SQL mode didn't solve my problem. I'll continue to investigate and update the question in case a development.</p>