为什么在此查询中不使用主键(集群键)?
我有一个SQL Server 2008 R2表,其表结构如下所示: CREATE TABLE [dbo].[CDSIM_BE] ( [ID] [bigint] NOT NULL, [EquipmentID] [varchar](50) NOT NULL, [SerialNumber] [varchar](50) NULL, [PyrID] [varchar](50) NULL, [MeasMode] [varchar](50) NULL, [ReadTime] [datetime] NOT NULL, [SubID] [varchar](15) NULL, [ProbePosition] [float] NULL, [DataPoint] [int] NULL, CONSTRAINT [PK_CDSIM_BE] PRIMARY KEY CLUSTERED ([ID] ASC, [EquipmentID] ASC, [ReadTime] ASC) WITH …