SQL选择多个不同的列行作为一列

Question

我不确定一个更好的方法来说明这一点,但我说我有一张桌子

name,    homephone,   fax,    mobile
========================================
bob,     123,         456,    999
chris,   null,        890,    null

我正在尝试创建一个SQL语句,它会让我这样

name,     phone
================
bob,      123
bob,      456
bob,      999
chris,    890

Answer 1

使用UNION怎么样？假设您的表名为目录.就像是:

SELECT name, homephone AS phone FROM Directory WHERE homephone IS NOT NULL
UNION
SELECT name, fax AS phone FROM Directory WHERE fax IS NOT NULL
UNION
SELECT name, mobile AS phone FROM Directory WHERE mobile IS NOT NULL