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declare @year int
set @year = 2009

while(year <= 2020)
begin

  SELECT A.dsformfieldvalue                              as Instrumento ,
         AVG(DATEDIFF(day, B.DTSTARTDATE , C.DTENDDATE)) as TempoMedio  ,
         'Jul/2009 a Dez/2009'                           as Periodo
  from       wfflow_form_field_log A
  right join wfflow_execute_task   B on A.codflowexecute = B.codflowexecute
  right join wfflow_execute_task   C on B.codflowexecute = C.codflowexecute
  where A.codflow  in (326, 439)
    and A.codfield =  2498
    and B.codtask  =  7064
    and C.codtask  =  7095
    and CONVERT(CHAR(4), B.DTSTARTDATE, 120) = @year
    and CONVERT(CHAR(4), B.DTSTARTDATE, 100) in ('Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec')

  set @year = @year + 1

  group by A.dsformfieldvalue

  union all

end

基本上我想要做的是大幅减少重复代码的数量，因为我必须合并一大堆选择。我正在尝试使用 while 循环，但它不起作用。有输入吗？

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2 回答 2

2

我想你想做的是这个

select * 
from wfflow_form_field_log A
     right join wfflow_execute_task B on 
          A.codflowexecute = B.codflowexecute
where year(b.dtstartdate) between 2009 and 2020
and month(b.dtstartdate)>=7
and ... -- other filters
于 2013-10-10T18:35:45.967 回答
0

您的 SQL 在语法上无效。select1语句的一般形式是

select <result-columns>
from <from-clause-including-joins>
where <where-criteria>
group by <group-by-criteria>
having <having-criteria>
order by <order-by-criteria>

union/的一般形式union all是

<select-statement>
UNION [ALL]
<select-statement>
...

其中每个 select 语句返回相同数量的列，并且每个 select 语句中的相应列具有相同的类型或隐式可转换为第一个 select 语句中列的类型的类型。

您已发表声明

set @year = @year + 1

所以它是select声明的一部分。

此外，您在后面添加了一个UNION ALLwith noselect语句。

解决这些问题，你应该会很好。但是......正如另一个答案指出的那样，您真正想做的是选择一系列年份。你不需要union: 你只需要合适的分组。

如果这是我的查询，我会做这样的事情（如果我正确理解你的意图）：

declare @dtFrom datetime = '2009-01-01 00:00:00.000' -- start of period
declare @dtThru datetime = '2020-12-31 23:59:59.996' -- end of period

select year             = datepart(year,b.dtstartdate) ,
       period           = case datepart(month,b.dtstartdate) / 6 when 1 then 'Jan-Jun' else 'Jul-Dec' end ,
       instrumento      = a.dsformfieldvalue ,
       tempomento       = avg( datediff(day, b.dtstartdate , c.dtenddate ) )
from       wfflow_form_field_log a
right join wfflow_execute_task   b on A.codflowexecute = B.codflowexecute
                                  and B.codtask        =  7064
                                  and b.dtStartDate between @dtFrom and @dtThru
right join wfflow_execute_task   d on B.codflowexecute = C.codflowexecute
                                  and C.codtask        =  7095
where A.codflow  in (326, 439)
  and A.codfield =  2498
group by datepart(year,b.dtStartDate) ,
         case datepart(month,b.dtstartdate) / 6 when 1 then 'Jan-Jun' else 'Jul-Dec' end ,
         A.dsformfieldvalue
order by 1,2,3 -- order by the first 3 columns (the grouping columns)

简单的！

于 2013-10-10T21:18:54.350 回答