title: EF Core 2.0 Npgsql : 42P01
body: <p>Im learning Postgresql with EF Core 2.0</p>
  
  <p><a href="https://i.stack.imgur.com/ZD065.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ZD065.png" alt="enter image description here"></a></p>
  
  <p>im keep getting this error. I searched on google but but I am not able to find the right answer.</p>
  
  <p>Here is some detail of my code ; 
  Startup.CS;</p>
  
  <pre><code>public void ConfigureServices(IServiceCollection services)
      {
          var connectionString =  @"User ID=postgres;Password=postgres;Host=localhost;Port=5432;Database=Test;";
  
          services.AddEntityFrameworkNpgsql()
              .AddDbContext&lt;DataContext&gt;(options =&gt; options.UseNpgsql(connectionString));
  
  
          services.AddMvc();
      }
  </code></pre>
  
  <p>and Data Context ;</p>
  
  <pre><code>public class DataContext : DbContext
  {
      public DataContext(DbContextOptions&lt;DataContext&gt; options) : base(options)
      {
      }
  
      public DbSet&lt;Questions&gt; Questions { get; set; }
  
  }
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/mfsYW.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/mfsYW.png" alt="enter image description here"></a></p>
  
  <p>and my model ;</p>
  
  <pre><code>public class Questions
  {
      public int Id { get; set; }
  
      public int studentId { get; set; } 
  
      public string Title { get; set; }
  
      public int Votes { get; set; }
  }
  </code></pre>
  
  <p>any help would be appreciated.</p>