title: django.db.utils.ProgrammingError: data type character varying has no default operator class for access method "gin"
body: <p>I am working on a django project, where I want to create gin indexing on my model's attribute.
  I want to create gin indexing on </p>
  
  <pre><code> SchoolName = models.CharField(max_length=200, blank=False, null=False)
  </code></pre>
  
  <p>But, I am getting this error </p>
  
  <pre><code> django.db.utils.ProgrammingError: data type character varying has no default operator class for access method "gin"
  </code></pre>
  
  <p>Help me to figure out this error</p>