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Paul Campbell
Paul Campbell
6,293 Points

Count one value in column but disregard if certain value is in the column

I have an organizer_id column, each organizer could hold many events and each event is either 'free event' or 'paid event' in an event_paid_type column.

Data set sample:

organizer_id      event_paid_type
9092720            free event
14360170           paid event
16167660            paid event
9092720            paid event
14360170           paid event
16167660           paid event

How do I answer this:

How many organizers had a least one paid order but never a free order?

I understand how to count up the paid events per organizer_id (which isn't honestly needed) but I don't know how to disregard an organizer_id if event_paid_type = 'free event'

My baby step:

SELECT organizer_id, event_paid_type, COUNT(*) as paid_event_count
FROM event_table
WHERE (event_paid_type = 'paid event')
GROUP BY organizer_id, event_paid_type
ORDER BY paid_event_count DESC;


organizer_id     event_paid_type     paid_event_count
9092720            paid event               1
14360170           paid event               2
16167660           paid event               2

2 Answers

Dana Johnson
Dana Johnson
7,952 Points

I haven't started the database track yet so I'm not sure, but could you try searching for exclusions in the WHERE search as well? IE:

WHERE event_paid_type = 'free event' && event_paid_type != 'free event'

or event just:

WHERE event_paid_type != 'free event'

changed comment to answer

Paul Campbell
Paul Campbell
6,293 Points

Oh my goodness Thanks Dana!

I could swear I tried that before and it failed but it is working!