本文介绍了SQL Select-转换列中的行的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
很基本,但是我现在被困住了.
Quite basic, but I am stuck at the moment.
在Informix数据库(无数据透视选项)上,我正在寻找一种动态方法来使用SQL转换下表:
On an Informix database (no pivot option), I am searching for a dynamic way to transform the following table using SQL:
book | info | value
-----------------------------
Moby Dick | price | high
Moby Dick | stock | few
Hamlet | price | low
Hamlet | stock | many
Faust | price | medium
Faust | stock | normal
结果表:
book | price | stock
-----------------------------
Moby Dick | high | few
Hamlet | low | many
Faust | medium | normal
感谢您的帮助!
推荐答案
您可以基于按书分组的CASE
表达式进行汇总.尝试这样的事情.
You can aggregate based on CASE
expression grouped by book. Try something like this.
SELECT book,
MAX(CASE WHEN info = 'price' THEN value END) as price,
MAX(CASE WHEN info = 'stock' THEN value END) as stock
FROM table1
GROUP BY book
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