title: Converting utf8_general_ci tables and fields to utf8_unicode_ci
body: <p>I have made a mistake when designing my application database several years ago and collation settings of my tables and table fields are mixed. Some of them are utf8_general_ci and some of them are utf8_unicode_ci.</p>
  
  <p>This causes problems when joining tables with different collations. Now, I am planning to change collation settings and make them the same: utf8_unicode_ci. I will be running these two SQL queries on all my tables.</p>
  
  <pre><code>ALTER TABLE  `table1` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;
  ALTER TABLE  `table1` CHANGE  `Action`  `Action` VARCHAR( 250 ) CHARACTER SET utf8 COLLATE utf8_unicode_ci NOT NULL;
  </code></pre>
  
  <p>My question is, does running these two SQL queries break any field values, especially the ones which contains accented characters? Or is it safe to run these two queries?</p>
  
  <p>Looking forward to hear from you. </p>
  
  <p>Thanks for your answers!</p>