title: mysql change innodb_large_prefix
body: <p>I just setup debian 8.3 on a VM and installed xampp after this <a href="http://www.debianhelp.co.uk/xampp.htm" rel="noreferrer">Tutorial</a>. Everything is working, until I tried to create a new table:</p>
  
  <pre><code>create table testtable
  (
    id int(10) not null auto_increment,
    firstname varchar(255) collate utf8mb4_german2_ci not null,
    lastname varchar(255) collate utf8mb4_german2_ci not null,
    primary key (id),
    unique key (lastname)
  )engine = innodb default charset=utf8mb4, collate=utf8mb4_german2_ci
  </code></pre>
  
  <p>I got the error: <code>#1709 - Index column size too large. The maximum column size is 767 bytes.</code>
  Then I found out this comes from the <code>prefix limitation</code> which is limited to 767Byte in <code>Innodb</code> and I can fix this by set the innodb_large_prefix in the my.cnf file. But I can't find the file, its not under <code>/etc/</code> and theres no <code>/etc/mysql/</code>-folder, the only <code>my.cnf</code> I found is in <code>/opt/lampp/etc/</code>, however, after I added the <code>innodb_large_prefix=1</code> to the file and restarted lampp. I stil get the same error. What did I do wrong? </p>
  
  <p><strong>edit</strong>: <code>SELECT version()</code> returns <code>5.6.14</code>, so <code>innodb_large_prefix</code> should be supported.</p>
  
  <p><strong>edit2</strong>: I know I can work around this by only set part of the the key as index to get under 767Byte. But I want to know here how to config the mysql correctly. </p>