Unable to map JSON properties: 42P01 - relation *** does not exist

[weitzhandler]

Hi,

I'm setting up a mini model and I'm getting this exception when executing the code from the docs website.

Here's my code:

  public class SomeEntity
  {
    public int Id { get; set; }
    [Column(TypeName = "jsonb")]
    public Customer Customer { get; set; }
  }

  public class Customer    // Mapped to a JSON column in the table
  {
    public string Name { get; set; }
    public int Age { get; set; }
    public Order[] Orders { get; set; }
  }

  public class Order       // Part of the JSON column
  {
    public decimal Price { get; set; }
    public string ShippingAddress { get; set; }
  }

using (var dbContext = services.GetRequiredService<AppDbContext>())
{
  await dbContext.Database.MigrateAsync();

  dbContext.SomeEntities.Add(
    new SomeEntity
    {
      Customer = new Customer
      {
        Name = "Roji",
        Age = 35,
        Orders = new[]
        {
          new Order { Price = 3, ShippingAddress = "Somewhere" },
          new Order { Price = 3, ShippingAddress = "Nowhere" }
        }
      }
    });

  await dbContext.SaveChangesAsync();
}

When I call SaveChanges, I get the following exception:

Npgsql.PostgresException:
42P01: relation "SomeEntities" does not exist

Here's a repro project.

[roji]

You're calling the MigrateAsync method, but your project doesn't have any actual migrations (those can be created with dotnet ef migrations add <name>. If you're just playing around, you likely want to call dbContext.Database.EnsureCreated instead, see this doc page.

Cross-posted as https://stackoverflow.com/questions/60856610/how-to-set-up-json-columns-with-npgsql

[weitzhandler]

Thanks and sorry for bothering.
Posted comment on SO as well:

I can see it when using the Npgsql VSIX, if I query SELECT * FROM SomeEntities, I get that error:

But if I execute SELECT * FROM public."SomeEntities", I get this error:

But I do get the results thereafter (when using public."SomeEntities"):

[weitzhandler]

roji transferred this issue from npgsql/npgsql yesterday
Oh, didn't realize the provider was an external repo, sorry.

Anyway, I keep on seeing this error in more occurrences in my project while migrating to Npgsql after calling MigrateAsync.

It helps if I substitute it with:

if (env.IsDevelopment())
  await appDbContext.Database.EnsureCreatedAsync();
else
  await appDbContext.Database.MigrateAsync();

But EF Core SQL provider respected the MigrateAsync call to create DB.

[roji]

@weitzhandler unfortunately, VS is quite limited (and problematic) in its support of non-SQL Server databases. I looked into the identifier quoting problem with the VS query generator (with the help of a Microsoft dev who really knows it), and this is a real limitation in the product. There's nothing really we can do (see #1320 (comment)).