title: How can I set COLLATION of a field to utf8_general_ci with GORM?
body: <p>I would like to have a string-type field in a MySQL database which is case-insenstive and unique. I used the following model:</p>
  
  <pre><code>type User struct {
      Id             int64  `json:"id" sql:"AUTO_INCREMENT"`
      Email          string `json:"email" sql:"unique_index"`
  }
  </code></pre>
  
  <p>which makes <code>Email</code> unique, but </p>
  
  <pre><code>type User struct {
      Id             int64  `json:"id" sql:"AUTO_INCREMENT"`
      Email          string `json:"email" sql:"unique_index;COLLATION(utf8_general_ci)"`
  }
  </code></pre>
  
  <p>seems to have no effect.</p>
  
  <p>How can I set COLLATION of a field to utf8_general_ci with GORM?</p>