如何在Oracle PL / SQL中使用varibles

Question

我正在尝试在Oracle中使用日期变量，我写了一个简单的声明，但它没有用，任何人都可以帮我解决这个问题，thx

谢

Declare 
StartDate Date := to_date('03/11/2017', 'dd/mm/yyyy');
Begin
SELECT
  REQUESTED_DATE.CALENDAR_DATE,
  Count( distinct FD_DW.SALES_HEADER_FACT.SALE_ID) INTO StartDate
FROM
  FD_DW.DATE_DIM  REQUESTED_DATE,
  FD_DW.SALES_HEADER_FACT
WHERE
  ( REQUESTED_DATE.DATE_KEY=FD_DW.SALES_HEADER_FACT.REQUESTED_DATE_KEY  )
  AND  
  REQUESTED_DATE.CALENDAR_DATE  = StartDate
GROUP BY
  REQUESTED_DATE.CALENDAR_DATE;
 End;

错误讯息：

Answer 1

试试这个

declare 
    StartDate Date := to_date('03/11/2017', 'dd/mm/yyyy');
    n_count integer; 
begin
select cnt INTO n_count from
( 
SELECT 
  REQUESTED_DATE.CALENDAR_DATE, 
  Count( distinct HEADER_FACT.SALE_ID) as cnt
FROM
  FD_DW.DATE_DIM          REQUESTED_DATE,
  FD_DW.SALES_HEADER_FACT HEADER_FACT
WHERE
  REQUESTED_DATE.DATE_KEY = HEADER_FACT.REQUESTED_DATE_KEY  and
  REQUESTED_DATE.CALENDAR_DATE  = StartDate
GROUP BY REQUESTED_DATE.CALENDAR_DATE
)
;
end;