Question

I asked this question before:

How do I bring back an entire range of dates in SQL between two dates, even when there is no data?

but I now need to only select incidents that have a Status of “E” for emergency.

I can’t put WHERE status=’E’ though, because that will stop it returning an entry for every single date.

How can I solve this?

Answer 1

Just add it to the LEFT OUTER JOIN ... ON, since this is a contition for the joined rows as far as I understand the question.

Something like this:

WITH DateRange(date) AS (
    SELECT @dateFrom dt
    UNION ALL
    SELECT DATEADD(dd, 1, date) date FROM DateRange WHERE date < @dateTo
)
SELECT DateRange.date, count(incident.id) 
FROM DateRange
LEFT OUTER JOIN incident
    ON incident.date >= DateRange.date 
    AND incident.date < DATEADD(dd, 1, DateRange.date)
    AND incident.status = 'E'
GROUP BY DateRange.date
ORDER BY DateRange.date