从更改的行记录中检索数据

Question

我在 Microsoft SQL Server 2005 Management Studio 工作。我是 T-SQL 的新手，我必须做以下报告：

我有一个 table (H2O)，其中包含时间戳、pumpstatus、tankVolume 的记录。

数据每 1 分钟插入 H2O。

我必须对清空罐进行报告（基于 date1 和 date2 之间的时间戳）。

排空过程开始时的指示器是泵状态从 2 变为 3

排空过程完成时的指示器是泵状态从 3 变为 2

感谢您的帮助！

Answer 1

试试这个：

;WITH cte (dt, st, v) AS 
(SELECT timestamp AS dt, status AS st, volume AS v
FROM h2o)
SELECT DISTINCT h.timestamp
, h.status
, h.volume
FROM cte c
INNER JOIN h20 h ON h.dt > c.dt AND ((c.st = 2 AND h.status = 3) OR (c.st = 3 AND h.status = 2))

您可以使用时间戳和状态列以及高于上一条记录的日期以及状态从 2 变为 3 或从 3 变为 2 时加入自身。

Answer 2

   ;WITH cte ([emptying time], [Initial Volume], Volume) AS 
        (SELECT      (SELECT TOP 1 H2O_1.[timestamp]
         FROM        [H2O] H2O_1
         WHERE       H2O_1.[H2O_TOOLS_P2_JY_TREND_VAL0] = 2 
         AND         H2O_1.[timestamp] < H2O_2.[timestamp]) AS [emptying time],
        (SELECT TOP 1 H2O_1.H2O_LT301_VOL_VAL0
         FROM       [H2O] H2O_1
         WHERE      H2O_1.[H2O_TOOLS_P2_JY_TREND_VAL0] = 2 
         AND        H2O_1.[timestamp] < H2O_2.[timestamp]) AS [Initial Volume],
         H2O_2.H2O_LT301_VOL_VAL0 As Volume         

         FROM        [H2O] H2O_2
         WHERE       H2O_2.H2O_TOOLS_P2_JY_TREND_VAL0 = 3
        )
   Select  Distinct c.[emptying time],
             max(c.[Initial Volume]) as [Initial Volume],                
             min(c.Volume) as [Final Volume],
             (max(c.[Initial Volume]) - min(c.Volume)) as [Emptying volume]
   from cte c
   group by  c.[emptying time]

从更改的行记录中检索数据

Retrieve data from changed rows records

sql

tsql

sql-server-2005