sql - 转置键值对 SQL 表

Question

我有一个由几列组成的表，包括一个键值对。所以想象一下：

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

我需要将其转换为以下格式：

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

像这样的东西？

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