Question

我试图在一个sql语句查询中获取今天，月到日，年初至今的行数（已输入）。但我不确定为什么它给了我所有三个相同的值。这是我的sql语句。

select BU,
count(CASE when a.date_added = trunc(sysdate) then (part) else '0' end) 
as TodayQuotes,
count(CASE when a.date_added > last_day(add_months(sysdate,-1)) then (part) else '0'     end) 
as MTDQuotesValue,
COUNT(case when to_number(to_char(a.date_added,'yyyy'))='2011' then (part) else '0' end) 
as YTDRegularValue
from articles
group by BU;

任何帮助将不胜感激

Answer 1

select BU,
       sum(CASE when a.date_added = trunc(sysdate) 
                then 1 
                else 0 
            end ) as TodayQuotes,
       sum(CASE when a.date_added > last_day(add_months(sysdate,-1)) 
                then 1 
                else 0 
            end) as MTDQuotesValue,
       sum(case when to_number(to_char(a.date_added,'yyyy'))='2011' 
                then 1 
                else 0 
            end) as YTDRegularValue
  from articles
 group by BU;

Answer 2

从"else '0'"表达式中删除CASE（隐含ELSE NULL}

COUNT计算所有NOT NULL个值，'0'为NOT NULL，因此对COUNT有所贡献。

计算SQL中case语句中的行

2 个答案: