[RESOLVED] SELECT colb if not colb SELECT cola?

Dolemite50

Hi,

If I have a table called names with the following:

userid
url_type
username
band_name

Is there a way to select the band_name and if !exists select the username in one statement? All entries contain username but not all contain band_name.

If this helps, url_type is set to 1 when a band_name is entered.

Thanks.

_RL_Ian

Why not just select both and then when you get the data back, if one is empty, display the other?

Dolemite50

Thanks a lot Ian,

That's pretty much what I've been doing. I'm a newbie setting out to optimize and read about only selecting the rows that I need so I was curious if there was an alternative. (i.e. is it faster to perform the "if" in mysql or php) I guess I'll stick with plan a, thanks. 🙂

Lars_Berg

select coalesce(band_name,user_name) as name, <otherColumns>
from t

Dolemite50

I like it!

Would you say that it would (in general) be faster than:

SELECT cola, colb FROM t...
cola={'cola']
$name={'colb']
if(!$name){
$name={'cola']
}

I'm hoping so, I can think of a lot of uses for that one, thanks.