So I have 3 entity classes:
public partial class Event
{
public Event()
{
Recurrences = new HashSet<Recurrence>();
}
public int Id { get; set; }
public ICollection<Recurrence> Recurrences { get; set; }
}
public partial class Recurrence
{
public Recurrence()
{
AspNetUsers = new HashSet<AspNetUser>();
}
public int Id { get; set; }
public int EventId { get; set; }
public ICollection<AspNetUser> AspNetUsers { get; set; }
}
public partial class AspNetUser
{
public AspNetUser()
{
Recurrences = new HashSet<Recurrence>();
}
public string Id { get; set; }
public string UserName { get; set; }
public ICollection<Recurrence> Recurrences { get; set; }
}
I would like to get the event given the aspnetuser.id using line to entity. so far this is what I have but it's returning an error:
// GET: api/Events?userId={userId}
public IQueryable<Event> GetEvents(string userId)
{
return db.Events
.Include(e => e.Recurrences
.Select(u => u.AspNetUsers.Where(i => i.Id == userId)));
}
When I exclude the where clause it works fine. Please help. Thanks in advance!
I don't think Include() means what you think it means. ( https://msdn.microsoft.com/en-us/library/bb738708%28v=vs.110%29.aspx ) What it does is tell the db set to be sure to bring in relationships for that object. By default (last I checked), the db context will auto pull in all relationships, so this isn't necessary. However, if you've turned off the lazy-loading ( http://www.entityframeworktutorial.net/EntityFramework4.3/lazy-loading-with-dbcontext.aspx ) then you'll need to .Include() all the relationships you want to have in the query.
This should solve your problem. I don't guarantee the SQL generated won't be silly, though.
If you have lazy-loading turned on:
db.Events.Include("Recurrences").Include("Recurrences.AspNetUsers")
.Where(e => e.Recurrences
.Any(r => r.AspNetUsers
.Any(u => u.Id ==userId)));
If you have lazy-loading turned off:
db.Events
.Where(e => e.Recurrences
.Any(r => r.AspNetUsers
.Any(u => u.Id ==userId)));
Also, if you have trouble seeing errors, you can .ToList() the query before returning so that it fails in your code and not deep inside the Web API stack. Personally, I like to do this so that I can try/catch the query and handle it properly.
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