Question

我有一个sql查询（下面），当表中不存在今天的日期时，该查询不起作用。如何强制它返回除日期字段中除今天日期之外没有值的空白行？这是一年多的回顾，但关键是看今天的日期。

select p.*
from [Apprise].[dbo].[adadjusttotal] c
--- Match
join (select distinct  a.adjustdate as curr_dte, max(b.adjustdate) over (partition by a.adjustdate) as prev_dte 
from [Apprise].[dbo].[adadjusttotal] a
join [Apprise].[dbo].[adadjusttotal] b  on year(a.adjustdate) -1 >= year(b.adjustdate) 
and month(a.adjustdate) >= month(b.adjustdate) 
and day(a.adjustdate) >=  day(b.adjustdate)
where a.adjustdate > getdate() -5 ) x
on c.adjustdate  = x.curr_dte
--- Prev Year
join [Apprise].[dbo].[adadjusttotal] p
on  p.adjustdate  = x.prev_dte               
where cast(c.adjustdate as date) = cast(getdate() as date)
and p.adjusttype = 'QuarterByDate'

Answer 1

在查询后添加：

if @@rowcount=0 
    select cast(getdate() as datetime),Null as col1,null as col2

或

if @@rowcount=0

    select convert(varchar(12), getdate(),101) as curdate, null as col1,null as col2

Answer 2

你可以这样做：

select p.*
from
(select 1 as dummy) x
outer apply (
    select p.*
    from [Apprise].[dbo].[adadjusttotal] c
    --- Match
    join (select distinct  a.adjustdate as curr_dte, max(b.adjustdate) over (partition by a.adjustdate) as prev_dte 
    from [Apprise].[dbo].[adadjusttotal] a
    join [Apprise].[dbo].[adadjusttotal] b  on year(a.adjustdate) -1 >= year(b.adjustdate) 
    and month(a.adjustdate) >= month(b.adjustdate) 
    and day(a.adjustdate) >=  day(b.adjustdate)
    where a.adjustdate > getdate() -5 ) x
    on c.adjustdate  = x.curr_dte
    --- Prev Year
    join [Apprise].[dbo].[adadjusttotal] p
    on  p.adjustdate  = x.prev_dte               
    where cast(c.adjustdate as date) = cast(getdate() as date)
    and p.adjusttype = 'QuarterByDate'
) p

由于这个外部数据总是与1行连接，所以当数据实际上不存在时，它也应该返回完全空行。

当然，对于您需要添加的任何默认值，您必须在select子句中执行此操作。 select p.*只是为了让它更短，而且我不知道你的专栏是什么。

当没有行存在时，查询需要返回行

2 个答案: