Grouping by Date but can't explain why?

I’ve only been using looker for about a month and have been learning through trial and error so far.

I’m really struggling to figure this one out. Just in a simple explore with 1 dimension and 1-3 measures.

dimension: service_shortname {
type: string
sql: ${TABLE}.service_shortname ;;
}

measure: good_minutes {
type: sum
sql: if(${TABLE}.avail_percent_minute>99,1,0) ;;
}

measure: total_minutes {
type: count
}

measure: availability_for_timespan{
type: number
sql: (${good_minutes}/${total_minutes}) ;;
}

If I add service_shortname and good_minutes it groups by shortname and I get what I expect:
service A. 200 minutes
service B. 900 minutes

Same is true if I use total_minutes.
Same is true if I use good_minutes and total minutes.

BUT, as soon as I try availability_for_timespan, it decides to group by day, then service_shortname so I get:

service A. 0.9
service A. 1

a row per day per shortname

Any thoughts…

Nevermind on this one, it had something to do with the link url that was part of the measure definition for availability_for_timespan. That link url was causing the sql to bring in a group by the date dimension_group, I wasn’t using that dimension in the explore, but because of the link it was still adding it.

Anyway I just created another measure without the link for this visualization, works now.

Don’t see a way to close or delete the question, sorry about that.