如何在T-SQL中将行转换为列，并将其写入临时表？

Question

This is a question maybe already asked.

My query is

SELECT Year, Month, Line, SUM(value) as total FROM myTable

I've the following query result table:

Year  Month   Line     Total
-------------------------------------------
2011     2      B1     5203510.00
2011     3      B1     2228850.00
2011     4      B1     7258075.00
2011     5      B1     6305370.00
2011     6      B1     5540180.00
2011     7      B1     7624430.00
2011     8      B1     4042300.00
2011     9      B1     3308870.00
2011    10      B1     4983875.00
2011    11      B1     4636500.00
2011    12      B1     3987350.00
2012     1      B1      518400.00

I would like the following:

Year Line  Jan    Feb   Mar   Apr ..... December

2011 B1      0    52035  2228 725 ..... 3987350
2012 B1     51840 ... ... .... 

Please, can you help me how to translate query SQL from rows to columns?

Answer 1

Essentially, you need to PIVOT your data. There are several examples on SO on how to do this. The tricky part is to convert the month number to a month name .

This is accomplished in the example with DATENAME(month, DateAdd(month, [Month], 0)-1)

SQL Statement

SELECT  *
FROM    ( 
          SELECT  Year, Line, Total, mnt = DATENAME(month, DateAdd(month, [Month], 0)-1)
          FROM    myTable
        ) mt          
PIVOT   (MAX(Total) FOR [mnt] IN ([January],[February],[March],[April],[May],[June],[July],[August],[September],[October],[November],[December])) AS PVT

Test script

;WITH myTable AS (
  SELECT * FROM (VALUES
    (2011     , 2      , 'B1',      5203510.00)
    , (2011     , 3      , 'B1',      2228850.00)
    , (2011     , 4      , 'B1',      7258075.00)
    , (2011     , 5      , 'B1',      6305370.00)
    , (2011     , 6      , 'B1',      5540180.00)
    , (2011     , 7      , 'B1',      7624430.00)
    , (2011     , 8      , 'B1',      4042300.00)
    , (2011     , 9      , 'B1',      3308870.00)
    , (2011    , 10      , 'B1',      4983875.00)
    , (2011    , 11      , 'B1',      4636500.00)
    , (2011    , 12      , 'B1',      3987350.00)
    , (2012     , 1      , 'B1',       518400.00)
  ) AS myTable (Year, Month, Line, Total)
)  
SELECT  *
FROM    ( 
          SELECT  Year, Line, Total, mnt = DATENAME(month, DateAdd(month, [Month], 0)-1)
          FROM    myTable
        ) mt          
PIVOT   (MAX(Total) FOR [mnt] IN ([January],[February],[March],[April],[May],[June],[July],[August],[September],[October],[November],[December])) AS PVT

Answer 2

What you're trying to do is pivot the data. I will just use the Month and Total (relevant) columns.

If you're using MS SQL 2008 or up:

SELECT [1] AS Jan, [2] AS Feb, .. [12] AS Dec,
       Total
FROM ( SELECT Month, Total FROM tableA ) AS SOURCE
PIVOT
( MAX(Total) AS Total
  FOR
  Month IN ([1],[2],...[12]) ) AS PIVOT

Answer 3

PIVOT是您寻求的T-SQL关键字。