title: Django seems to truncate strings in MYSQL's longtext type column
body: <p>I have a MySQL <code>longtext</code> field, that corresponds to the following field in a Django model:</p>
  
  <pre><code>class MyModel(models.Model):
      # some other fields
      my_long_text_field = models.TextField(blank=True, null=True)
  </code></pre>
  
  <p>The problem is that Django seems to truncate my string when I am trying to save data (a unicode string with around 40k characters) to database. I have come across a <a href="https://stackoverflow.com/questions/32516026/how-to-create-double-and-long-text-field-from-django-models">question</a> where they say that models.TextField corresponds to MySQL <code>longtext</code>. </p>
  
  <p>Then why does this data truncating happening ? What I am doing wrong ?</p>