title: mysql_tzinfo_to_sql - updating the timezone tables after you already loaded them and other questions
body: <p>I just used mysql_tzinfo_to_sql to load the zoneinfo database into mysql.  They all imported fine.</p>
  
  <pre><code>[root@db ~]# mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql mysql
  </code></pre>
  
  <p>I have some questions that I can't seem to find answers for :</p>
  
  <ul>
  <li>Are the names in <code>time_zone_name</code> the same as those used in PHP?  I am assuming PHP uses the same <code>/usr/share/zoneinfo</code> information so the names would be the same as well right?</li>
  <li>It mentions the tables need to be repopulated every now and then when timezone data changes.  Is this when tzdata is updated though <code>yum</code> updates?  Is <code>tzdata</code> my <code>/usr/share/zoneinfo</code> information?</li>
  <li>If the above is true, tzdata updates, and I need to repopulate my tables... how do I do that?  Can I just run <code>[root@db ~]# mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql mysql</code> again?  Will that command overwrite the information that is currently there or do I need to manually delete all the table entries before doing so?</li>
  </ul>
  
  <p>Thanks for any information on the above.  So far the timezone names used in PHP seem to match up, but I have not looked into it further other than a few tests.  As for the last two... I am just trying to get ahead of things so if/when the tables need updated I do not have trouble.</p>