计算太阳 od 日期时间时出错

Question

SELECT *, 
  ROW_NUMBER() OVER (ORDER BY checktime)RN 
INTO   XYZZ
FROM   test 
where  checktime>='2013-08-14 00:00:00.000' 
  and  checktime<='2013-08-14     23:00:00.000'     

........1

SELECT t1.*, 
  ( t2.checktime - t1.checktime) as w
FROM   XYZZ t1 
LEFT JOIN XYZZ t2 ON t1.RN = t2.RN - 1
union all
select null,null,null,null,null,null,null,null,null,
  Convert(varchar(10),sum(DatePart(hh,w)))+':'+
  Convert(varchar(10),sum(DatePart(mi,W)))
From XYZZ

...2

1. 工作正常，但 2 不工作

我在 sql 中执行这个查询，我得到这个错误：

消息 207，级别 16，状态 1，行 10 列名“w”无效。消息 207, 第 16 级，状态 1，第 11 行 列名“W”无效。

Answer 1

你不能那样做，你不能在 UNION ALL 之后的第二个查询中引用别名，它们被单独处理，但你可以这样做：

SELECT t1.*, (t2.checktime - t1.checktime) as w
FROM   XYZZ t1 
LEFT JOIN XYZZ t2 ON t1.RN = t2.RN - 1
UNION ALL
SELECT null,null,null,null,null,null,null,null,null,
  Convert(varchar(10),sum(DatePart(hh,w)))+':'+
  Convert(varchar(10),sum(DatePart(mi,W)))
From
(
    SELECT t1.*, (t2.checktime - t1.checktime) as w
    FROM   XYZZ t1 
    LEFT JOIN XYZZ t2 ON t1.RN = t2.RN - 1
) AS t;

或

WITH CTE
AS
(
    SELECT t1.*, (t2.checktime - t1.checktime) as w
    FROM   XYZZ t1 
    LEFT JOIN XYZZ t2 ON t1.RN = t2.RN - 1
)
SELECT *
FROM CTE
UNION ALL
SELECT null,null,null,null,null,null,null,null,null,
  Convert(varchar(10),sum(DatePart(hh,w)))+':'+
  Convert(varchar(10),sum(DatePart(mi,W)))
FROM CTE;