public async Task<IEnumerable<Measurement>> GetLastMeasurementForEachSensor()

{

var groupedMaxDateTime = AsQueryable()

.GroupBy(m => m.SensorId)

.Select(m => new

{

SensorId = m.Key,

SensorDateTime = m.Max(y => y.SensorDateTime)

});

var dmMeasurements = await AsQueryable()

.Join(groupedMaxDateTime,

(DmMeasurement a) => new { a.SensorId, a.SensorDateTime },

b => new { b.SensorId, b.SensorDateTime },

(a, b) => a

)

.Select(x => new DmMeasurement {

SensorId = x.SensorId,

ReceivedAt = x.ReceivedAt,

ReceivedValue = x.ReceivedValue

})

.ToListAsync();

return dmMeasurements.Select(x => x.ToDomain(true));

}

public async Task<IEnumerable<Measurement>> GetLastMeasurementForEachSensor() { var groupedMaxDateTime = AsQueryable() .GroupBy(m => m.SensorId) .Select(m => new { SensorId = m.Key, SensorDateTime = m.Max(y => y.SensorDateTime) }); var dmMeasurements = await AsQueryable() .Join(groupedMaxDateTime, (DmMeasurement a) => new { a.SensorId, a.SensorDateTime }, b => new { b.SensorId, b.SensorDateTime }, (a, b) => a ) .Select(x => new DmMeasurement { SensorId = x.SensorId, ReceivedAt = x.ReceivedAt, ReceivedValue = x.ReceivedValue }) .ToListAsync(); return dmMeasurements.Select(x => x.ToDomain(true)); }

public async Task<IEnumerable<Measurement>> GetLastMeasurementForEachSensor()
{
	var groupedMaxDateTime = AsQueryable()
		.GroupBy(m => m.SensorId)
		.Select(m => new
		{
			SensorId = m.Key,
			SensorDateTime = m.Max(y => y.SensorDateTime)
		});
	var dmMeasurements = await AsQueryable()
		.Join(groupedMaxDateTime,
			(DmMeasurement a) => new { a.SensorId, a.SensorDateTime },
			b => new { b.SensorId, b.SensorDateTime },
			(a, b) => a
		)
		.Select(x => new DmMeasurement {
			SensorId = x.SensorId,
			ReceivedAt = x.ReceivedAt,
			ReceivedValue = x.ReceivedValue
		})
		.ToListAsync();
	return dmMeasurements.Select(x => x.ToDomain(true));
}

293300cookie-checkC# linq group by multiple columns