kettle如何實現列轉行

本文主要記錄kettle列轉行控件的使用。

 

 原數據：

    目標數據：

 

 

1、用例腳本

create TABLE studentInfo
(
    studentno int,
    Cname varchar(10),
    grade int
);
insert into studentInfo values(2018100,'語文',81);
insert into studentInfo values(2018100,'數學',82);
insert into studentInfo values(2018100,'英語',83);

insert into studentInfo values(2018101,'語文',71);
insert into studentInfo values(2018101,'數學',71);
insert into studentInfo values(2018101,'英語',72);

insert into studentInfo values(2018102,'語文',91);
insert into studentInfo values(2018102,'數學',92);
insert into studentInfo values(2018102,'英語',93);


INSERT INTO studentInfo VALUES(2018103,'語文',60);
INSERT INTO studentInfo VALUES(2018103,'數學',61);
INSERT INTO studentInfo VALUES(2018103,'英語',94);
commit;

ktr文件如下所示：

 

 

表輸入

 

 

SELECT studentno,Cname,grade FROM studentInfo order by studentno

列轉行

 

 

 

excel文件輸出

 

 

運行后，excel文件內容

 

 

 

相當於sql語句：

SELECT *
FROM
(SELECT studentno, cname,grade
    FROM studentInfo) AS SourceTable
PIVOT
(
AVG(grade)
FOR Cname IN ([語文], [數學], [英語])
) AS PivotTable;

附： UNPIVOT

select * from () sourceTable UNPIVOT (計算列 for 新列名 in 原列名list) as UPV

例如：--Unpivot the table.
SELECT VendorID, Employee, Orders
FROM
   (SELECT VendorID, Emp1, Emp2, Emp3, Emp4, Emp5
   FROM pvt) p
UNPIVOT
   (Orders FOR Employee IN
      (Emp1, Emp2, Emp3, Emp4, Emp5)
)AS unpvt;
GO