SQL: Count distinct values from one column based on multiple criteria in other columns

Question

I am trying to do count distinct values based on multiple criteria. Sample data exercise included below.

           Table1
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Answer 1

You can have a conditional count(distinct) by using this code:

SELECT Test, COUNT(DISTINCT "Bug ID") AS "Total Bugs",
count(distinct (CASE WHEN "Status" <> 'Closed' THEN "Bug ID" END)) as "Open Bugs"
FROM Table1
GROUP BY Test

The case statement checks the condition. When true, it returns the Bug ID. When not present, it defaults to NULL, so the id does not get counted.