title: Model does not have primary keys
body: <p>I'm using <a href="https://github.com/go-pg/pg" rel="nofollow noreferrer">https://github.com/go-pg/pg</a> for my PostegreSQL database and Go. I'm trying to get the value of a table <code>Settings</code> that has the column <code>site_name</code> but for some reason it is giving me the error <code>panic: model=Settings does not have primary keys</code></p>
  
  <pre><code>package mypackage
  
  import (
      "database"
  )
  
  type Settings struct {
      SiteName string
  }
  
  func Get() string {
      var name Settings
  
      err := Db.Model(&amp;name).First()
      if err != nil {
          panic(err)
      }
  
      return name.SiteName
  }
  </code></pre>
  
  <p>I don't have the experience to really understand what's going on here or how to fix it. Any solutions? Thanks!</p>
  
  <p>Example (FirstRow): <a href="https://godoc.org/github.com/go-pg/pg#DB.Select" rel="nofollow noreferrer">https://godoc.org/github.com/go-pg/pg#DB.Select</a></p>