Select another field in mysql if field is set to null?

Question

I want select displayname as username

if username = null and if username is NOT NULL then select username as username

eg.

id username displayname
1   xyz       NULL
2   NULL      abc

How can I do this in one select declaration ... Thanks

+2

halocursed 18 oct. At 11:57

1 answer

elder_george · Accepted Answer · 2009-10-18T12:02:36+0000

coalesce (username, dispalyname) should help you.

eg:.

select coalesce(username, dispalyname) from users
where ...