Question

在SQL存储过程中可以这样做吗？或者我必须有3个单独的程序？这是单独的，但现在我只得到一个错误：关键字附近的语法不正确＆＃39;介于＆＃39;。

FROM table a

WHERE
field1 = 'asd'
and field2 is null
and field3  not in ('a','b','c') 
and

case @input

when 'now' then
    (a.datefield between dateadd(day, -31, getdate()) and getdate())
when '24_hour' then
    (a.datefield between getdate() and dateadd(hour, 24, getdate()))
when '3_days' then
    (a.datefield between getdate() and dateadd(day, 3, getdate()))
end

order by a.datefield asc
end

Answer 1

有几种方法可以实现这一目标。以下是一种可能性：

case
    when @input ='now' and (a.datefield between dateadd(day, -31, getdate()) and getdate()) then 1
    when @input ='24_hour' and (a.datefield between getdate() and dateadd(hour, 24, getdate())) then 1
    when @input ='3_days' and (a.datefield between getdate() and dateadd(day, 3, getdate())) then 1
    else 0        
end = 1

对于最大的scalabilty，我可能会看一下TVC：

FROM table a
join (values 
        ('now',dateadd(day, -31, getdate()),getdate()),
        ('24_hour',getdate(),dateadd(hour, 24, getdate())),
        ('3_days',getdate(),dateadd(day, 3, getdate()))
     ) t(input,startdate,enddate) 
on t.input = @input
WHERE
field1 = 'asd'
and field2 is null
and field3  not in ('a','b','c') 
and a.datefield between t.startdate and t.enddate

Answer 2

您也可以完全替换case语句，并且只使用where where子句中的AND和OR运算符。这样的事情......

FROM table a

WHERE field1 = 'asd'
and   field2 is null
and   field3  not in ('a','b','c') 
and 
   (
    (@input ='now'     AND a.datefield between getdate()-31 and getdate())
    OR
    (@input ='24_hour' AND a.datefield between getdate() and dateadd(hour, 24, getdate()))
    OR
    (@input ='3_days'  AND a.datefield between getdate() and  getdate()+3)
   )
order by a.datefield asc

SQL存储过程案例何时

2 个答案: