[Solved] How to convert linq query to non-query expression?

If you want to convert this to the method syntax version, you can do this step by step. I like to start at the end and work through to the beginning:

1. select to Select defines the source:

   .Select(g => g.OrderByDescending(s => s.MeasureDate).FirstOrDefault());
   

2. group is GroupBy:

   .GroupBy(s => s.SensorUnitId)
   .Select(g => g.OrderByDescending(s => s.MeasureDate).FirstOrDefault());
   

3. from the source

   SensorObservationEntities.SensorsMeasures
   .GroupBy(s => s.SensorUnitId)
   .Select(g => g.OrderByDescending(s => s.MeasureDate).FirstOrDefault());