title: EF migrations Code First. Add column to database if column doesn't exist
body: <p>I need to add a column to a table if that column doesn't exist. Reason: in some database we have such column and in some - not. I've added field to my model and create migration:</p>
  
  <pre><code>public override void Up()
  {           
      AddColumn("dbo.NavFilters", "Promo", c =&gt; c.String(maxLength: 100, nullable:true));
  }
  
  public override void Down()
  {
      DropColumn("dbo.NavFilters", "Promo");
  }
  </code></pre>
  
  <p>How can I check is the column exists?</p>