MySQL select where column is not empty

2018-07-03 19:57:13

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

For example, I have the following query:

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.

Compare value of phone2 with empty string:

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

Note that NULL value is interpreted as false .

To check if field is NULL use IS NULL , IS NOT NULL operators.

MySql reference http://dev.mysql.com/doc/refman/5.0/en/working-with-null.html

Check for NULL and empty string values:

select phone
, phone2 
from users 
where phone like '813%' 
and trim(coalesce(phone2, '')) <>''

NB I think COALESCE() is SQL standard(-ish), whereas ISNULL() is not.

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