实体框架6存储过程只返回一个项目（记录）

Question

我有以下存储过程（每小时返回一台机器的事件数）：

CREATE PROCEDURE sp_ReceivedEventsPerTimePerMachine 
    @dateFrom datetime,  
    @dateTo datetime, 
    @machineId uniqueidentifier
AS
    IF DATEPART(MINUTE, @dateFrom) != 0 OR DATEPART(SECOND,@dateFrom)!= 0 OR DATEPART(MILLISECOND,@dateFrom)!= 0
        RAISERROR ('dateFrom exceeds maximum precision. Only full hours are allowed.', 16, 1)
    IF DATEPART(MINUTE, @dateTo) != 0 OR DATEPART(SECOND,@dateTo)!= 0 OR DATEPART(MILLISECOND,@dateTo)!= 0
        RAISERROR ('dateTo exceeds maximum precision. Only full hours are allowed.', 16, 1)

    IF (@@ERROR = 0) 
        SELECT  
            DATEADD(hh, DATEPART(hh, ReceiveDateTime), DATEADD(day, day(ReceiveDateTime) - 1, DATEADD(month, month(ReceiveDateTime) - 1, DATEADD(Year, year(ReceiveDateTime) - 1900, 0)))) AS DateTime, 
            COUNT(*) AS [NumberOfEvents] 
        FROM 
            ReceivedEvents 
        WHERE 
            ReceiveDateTime BETWEEN @dateFrom AND @dateTo 
            AND MachineId = @machineId
        GROUP BY  
            DATEADD(hh, DATEPART(hh, ReceiveDateTime), DATEADD(day, day(ReceiveDateTime) - 1, DATEADD(month, month(ReceiveDateTime) - 1, DATEADD(Year, year(ReceiveDateTime) - 1900, 0))))
        ORDER BY 
            DateTime

我使用EF6执行程序，这是我的C＃代码：

var result = await Context.Database.SqlQuery<EventsPerDateTime>( "sp_ReceivedEventsPerTimePerMachine @dateFrom, @dateTo, @machineId",
    new SqlParameter( "dateFrom", fromDateTime ), new SqlParameter( "dateTo", toDateTime ), new SqlParameter( "machineId", machine.MachineId ) )
        .ToListAsync();

使用EF执行过程始终只返回一条记录，但该过程返回多个值。直接执行该过程（使用SQL Management Studio）返回多个记录。

如何使用EF获取select语句返回的所有记录？

修改

这是我的完整代码

以下是EventsPerDateTime类：

public class EventsPerDateTime
{
    public DateTime DateTime { get; set; }
    public Int32 NumberOfEvents { get; set; }
}

用于抽象EF的服务

public class SqlService<TContext> : Disposable, ISqlService<TContext>
    where TContext : DbContext, new()
{
    private TContext _context;
    private TContext Context
    {
        get
        {
            if ( _context == null )
            {
                Logger.Debug( "Request DbContext form database factory." );
                _context = DatabaseFactory.GetDb();
            }
            return _context;
        }
    }

    public IDatabaseFactory<TContext> DatabaseFactory { get; }

    public SqlService( IDatabaseFactory<TContext> databaseFactory, ILoggerFactory loggerFactory )
        : base( loggerFactory.CreateLogger( typeof (SqlService<TContext>) ) )
    {
        Logger.Trace( "Enter Ctor - Exit on next line." );
        DatabaseFactory = databaseFactory;
    }

    protected override void Disposed()
    {
        if ( _context != null )
            _context.Dispose();
    }

    public DbRawSqlQuery<TElement> SqlQuery<TElement>( String sql, params Object[] parameters )
    {
        return Context.Database.SqlQuery<TElement>( sql, parameters );
    }

    public DbRawSqlQuery SqlQuery( Type elementType, String sql, params Object[] parameters )
    {
        return Context.Database.SqlQuery( elementType, sql, parameters );
    }

    public Int32 ExecuteSqlCommand( String sql, params Object[] parameters )
    {
        return Context.Database.ExecuteSqlCommand( sql, parameters );
    }

    public Int32 ExecuteSqlCommand( TransactionalBehavior transactionalBehavior, String sql, params Object[] parameters )
    {
        return Context.Database.ExecuteSqlCommand( transactionalBehavior, sql, parameters );
    }

    public async Task<Int32> ExecuteSqlCommandAsync( String sql, params Object[] parameters )
    {
        return await Context.Database.ExecuteSqlCommandAsync( sql, parameters );
    }

    public async Task<Int32> ExecuteSqlCommandAsync( TransactionalBehavior transactionalBehavior,
                                                     String sql,
                                                     params Object[] parameters )
    {
        return await Context.Database.ExecuteSqlCommandAsync( transactionalBehavior, sql, parameters );
    }

    public async Task<Int32> ExecuteSqlCommandAsync( String sql,
                                                     CancellationToken cancellationToken,
                                                     params Object[] parameters )
    {
        return await Context.Database.ExecuteSqlCommandAsync( sql, cancellationToken, parameters );
    }

    public async Task<Int32> ExecuteSqlCommandAsync( TransactionalBehavior transactionalBehavior,
                                                     String sql,
                                                     CancellationToken cancellationToken,
                                                     params Object[] parameters )
    {
        return await Context.Database.ExecuteSqlCommandAsync( transactionalBehavior, sql, cancellationToken, parameters );
    }

对服务的调用

var toDateTime = DateTime.Now.Date.AddHours( DateTime.Now.Hour );
var fromDateTime = toDateTime.Subtract( Parameters.ReceivedEventsOfLastHours.ToHours() );
var result =
    await SqlService.SqlQuery<EventsPerDateTime>( "sp_ReceivedEventsPerTimePerMachine @dateFrom, @dateTo, @machineId",
                                                  new SqlParameter( "dateFrom", fromDateTime ),
                                                  new SqlParameter( "dateTo", toDateTime ),
                                                  new SqlParameter( "machineId", machine.MachineId ) )
                    .ToListAsync();

生成的SQL（使用SQL Server Profiler捕获）：

exec sp_executesql 
N'sp_ReceivedEventsPerTimePerMachine @dateFrom, @dateTo, @machineId',
N'@dateFrom datetime,@dateTo datetime,@machineId uniqueidentifier',
@dateFrom='2015-10-19 22:00:00',@dateTo='2015-10-21 22:00:00',@machineId='B0BDD062-0178-E511-9BD8-801F02F47041'