GroupBy on Navigation Property not translating properly

[nomz0101]

Hi,

When writing a simple groupBy the query that gets translated adds extra join of the same table when aggregating on navigation property that is also used in the Key.
This does not make sense and causes a lot of performance issues.

C#:

_session.Set<SchoolLoginLocation>()
                .GroupBy(a => new { a.LoginLocation.Id })
                .Select(g => new { g.Key, Cnt = g.Count(a => a.LoginLocation.Id == 1) })
                .ToList();

SQL Translation:

SELECT [l].[Id] AS [LocationId], COUNT(CASE WHEN [l0].[Id] = 1 THEN 1 END) AS [Cnt]
FROM [bdk].[SchoolLoginLocations] AS [s]
**INNER JOIN [bdk].[LoginLocations] AS [l] ON [s].[LoginLocationId] = [l].[Id]
INNER JOIN [bdk].[LoginLocations] AS [l0] ON [s].[LoginLocationId] = [l0].[Id]**
GROUP BY [l].[Id]