MySQL选择哪个列不是空的。

In MySQL, can I select columns only where something exists?

在MySQL中，我可以只在存在的地方选择列吗?

For example, I have the following query:

例如，我有以下查询:

select phone, phone2
from jewishyellow.users
where phone like '813%'
and phone2

I'm trying to select only the rows where phone starts with 813 and phone2 has something in it.

我试着只选择以813开头的行，而phone2有一些内容。

10 个解决方案

215

Compare value of phone2 with empty string:

用空字符串比较phone2的值:

select phone, phone2 
from jewishyellow.users 
where phone like '813%' and phone2<>''

Note that NULL value is interpreted as false.

注意，NULL值被解释为false。