sql - 转置键值对 SQL 表

Question

我有一个由几列组成的表，包括键值对。想象一下:

BookID, Key, Value
MyBook, Price, 19.99
MyBook, ISBN, 987878495793
MyBook, Pages, 354
MyBook2, ...., ....
MyBook2, ...., ....

我需要将其转化为以下格式:

BookID, Price, ISBN, Pages
MyBook, 19.99, 987878495793, 354
MyBook2,.....,.............,....

即转置单元格 - 我将如何在 SQL 中执行此操作？

Answer 1

是这样的吗？

SELECT
  BookID, Price, ISBN, Pages
FROM
(
  SELECT BookID, Key, Value FROM yourTable
)
  AS SourceTable
PIVOT
(
  SUM(Value) FOR Key IN (Price, ISBN, Pages)
)
  AS PivotTable
ORDER BY
  BookID

http://technet.microsoft.com/en-us/library/ms177410(SQL.105).aspx