Question

我有一个表Temp，Date作为主键 - 每天一行，大约2年的行。我想将8/1/2017的CY实际卷复制到9/1/2017，依此类推8月份（尽管我希望能够运行此SQL，但仍保持这个问题的简单性）也复制其他数据）。

因此，9/1/2017应该有200，等等整个月。

Date,  Pipeline,  CY Actual Volume

8/1/2017,      XX,         200

8/2/2017,      YY,        100

.....


9/1/2017,      XX,          0

9/2/2017,  YY,     0
.
.

我有以下SQL，但它不能正常运行（它确实运行并且给了我受影响的行数，但没有任何变化）。

update cy
set cy.[CY Actual Volume] = ny.[CY Actual Volume]
from [dbo].[Temp] cy 
left join [dbo].[Temp] ny on dateadd(day, 31, cy.Date) = ny.Date
                          and cy.[Pipeline] = ny.[Pipeline] 
where cy.[CY Actual Volume] = 0 
  and year(ny.Date) = 2017

Answer 1

试试这个

DECLARE @temp TABLE (myDate DATETIME, pipeline VARCHAR(2), cy INT)
INSERT INTO @temp( myDate, pipeline, cy )VALUES  ( '2017-08-01', 'XX', 200 )
INSERT INTO @temp( myDate, pipeline, cy )VALUES  ( '2017-08-02', 'YY', 100 )

DECLARE @target TABLE (myDate DATETIME, pipeline VARCHAR(2), cy INT)
INSERT INTO @target( myDate, pipeline, cy )VALUES  ( '2017-09-01', 'XX', 0 )
INSERT INTO @target( myDate, pipeline, cy )VALUES  ( '2017-09-02', 'YY', 0 )    

UPDATE @target SET cy = [@temp].cy FROM @temp WHERE DATEADD(MONTH,-1, [@target].myDate) = [@temp].myDate

SELECT * FROM @temp
SELECT * FROM @target

Answer 2

CREATE TABLE Volume
(
    Date date not null primary key,
    Pipeline nvarchar(50) not null,
    CY int not null
)

go

--delete Volume;

insert into Volume
    (Date, Pipeline, CY)
VALUES
    ('2017-08-01', 'XX', 200),
    ('2017-08-02', 'YY', 100),
    ('2017-09-01', 'XX', 0),
    ('2017-09-02', 'YY', 0);

update v1
set
    v1.CY = v2.CY
output inserted.Date, inserted.Pipeline, deleted.CY as OldCY, inserted.CY as NewCY 
from
    Volume as v1 inner join Volume as v2
        on (DATEADD(MONTH, -1, v1.Date) = v2.Date and MONTH(v2.Date) = 8 and YEAR(v2.Date) = 2017)

将表中行的数据复制到同一表中的未来行

2 个答案: