title: One Save function rather than Insert and Update in my repository
body: <p>Is there any downside to having a save function that does both updating or inserting rather than using separate Update and Insert functions in my repos?</p>
  
  <p><strong>Below is my save function in my CustomerRepository:</strong></p>
  
  <pre><code>// save
  public void Save(Model.Customer customer)
  {
      if (customer.Id == 0)
      {
          context.Customers.Add(Mapper.Map&lt;Data.Customer&gt;(customer));
      } 
      else
      {
          context.Entry(Mapper.Map&lt;Data.Customer&gt;(customer)).State = EntityState.Modified;
      }
      context.SaveChanges();
  }
  </code></pre>