Configure a non-shadow principal key for this relationship

Question

I'm trying to build by database using Code first Entity framework, within a ASP Core 1, RC2 projects.

And I get this error message:

The key {'TempId'} contains properties in shadow state and is referenced by a relationship from 'TaskStatus' to 'TaskRunner.IsRunning'. Configure a non-shadow principal key for this relationship.

Any one have a idea on what this error means?

Note that I don't have ny column name tempId. I guest that EF7 build this column for itself.

Here is my entity

 public class TaskStatus
 {
        public Guid TaskConfigId { get; set; }
        public string LastResultValue { get; set; }
        public int RetryCount { get; set; }
        public TaskStatusEnum StatusEnum { get; set; }
        public DateTimeOffset LastUpdate { get; set; }
        public TaskResult TaskResult { get; set; }
        public TaskStatusEnum TaskStatusEnum { get; set; }
}

public class TaskRunner
{
    public DateTimeOffset RunAt { get; set; }
    public TaskConfig TaskConfig { get; set; }
    public Guid TaskConfigId { get; set; }
    public TaskStatus IsRunning { get; set; }
}

Answer 1

I was able to fix this by manually specifying a property as the primary key on my models. You might try putting a [Key] attribute on TaskConfigId, and maybe adding a primary key field to TaskRunner.

This bug report alludes that using Navigation Properties requires explicit primary keys, rather than letting EF trying to decide which property is the PK based on naming conventions.

I believe Shadow Properties simply means the properties (table columns) that are created to support navigation properties, for example a column named IsRunningTaskStatusId on your TaskRunner table, which contains the primary key of the associated TaskStatus. https://docs.efproject.net/en/latest/modeling/shadow-properties.html