MS SQL

Question

我尝试了以下查询：

SELECT Name,startdate,address from employee

我得到的数据是这样的：

Name  StartDate Address
John   01/01/2017   na

虽然我想要这样的数据：

Name      | John
------------------------
StartDate | 01/01/2017
Address   |  NA

如何编写正确的查询以获得预期的结果？

Answer 1

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可以更容易（更快）地旋转列

IF OBJECT_ID('tempdb..#TestData', 'U') IS NOT NULL 
DROP TABLE #TestData;

CREATE TABLE #TestData (
    f_Name VARCHAR(10),
    StartDate DATE,
    Address VARCHAR(30)
    );
INSERT #TestData(f_Name, StartDate, Address)
VALUES ('Johm', '2017-01-01', 'n/a');

--=================================================

SELECT 
    cav.ColLabel, 
    cav.ColValue
FROM
    #TestData td
    CROSS APPLY ( VALUES 
        (1, 'Name', td.f_Name),
        (2, 'StartDate', CAST(td.StartDate AS VARCHAR(10))),
        (3, 'Address', td.Address)
        ) cav (SortVal, ColLabel, ColValue)
ORDER BY
    cav.SortVal;

结果...

ColLabel  ColValue
--------- ------------------------------
Name      Johm
StartDate 2017-01-01
Address   n/a