在SQL之前和之后选择一天

Question

I have the following stored procedure:

create procedure spListing
    (@oMonth int, @oYear int)
AS
BEGIN
    SELECT oDate, oValue 
    FROM oTable 
    WHERE DATEPART(MONTH, oDate) = @oMonth 
      AND DATEPART(YEAR, oDate) = @oYear
END

It will select all the value with selected month and year base on given parameter.

I want to select 1 day before and after base on given parameter.

For example: if @oMonth = '9' and @oYear = '2014' then it will show a list from 31 Aug 2014 until 1 Oct 2014.

Does anyone know how to achieve this?

Thank you.

Answer 1

First find the two dates between which you need to get the data.

DECLARE @oMonth INT=9,
        @oYear  INT=2014,
        @date   DATE

SELECT @date = Cast (CONVERT(VARCHAR(4), @oYear) + '-'
                     + CONVERT(VARCHAR(2), @oMonth) + '-01' AS DATE)

SELECT Dateadd(day, -1, @date) -- 2014-08-31(Startdate)
SELECT Dateadd(day, 1, Dateadd(day, -Day(@date), Dateadd(month, 1, @date))) --2014-10-01 (Endate)

Now you can use the above queries to filter your result. Change your SP like this.

CREATE PROCEDURE Splisting (@oMonth INT,
                            @oYear  INT)
AS
  BEGIN
      DECLARE @date DATE

      SELECT @date = Cast (CONVERT(VARCHAR(4), @oYear) + '-'
                           + CONVERT(VARCHAR(2), @oMonth) + '-01' AS DATE)

      SELECT oDate,
             oValue
      FROM   oTable
      WHERE  oDate BETWEEN Dateadd(day, -1, @date) 
                   AND Dateadd(day, 1, Dateadd(day, -Day(@date), Dateadd(month, 1, @date)))
  END 

Answer 2

I belive this answers your question:

CREATE PROCEDURE spListing
(@oMonth int, @oYear int)
AS
BEGIN
   DECLARE @day int = 1;
   DECLARE @startDate date =  DATEADD(day,-1,DATEADD(mm, (@oYear - 1900) * 12 + @oMonth - 1 , @day - 1))
   DECLARE @endDate date =  DATEADD(month,1,DATEADD(mm, (@oYear - 1900) * 12 + @oMonth - 1 , @day - 1))

   SELECT oDate, oValue 
   FROM oTable WHERE oDate 
   BETWEEN @startDate AND @endDate 
END