7 Day Users Stat SQL Query

Can someone help me with a SQL Query that will display all users that have made a post every day for the last 7 days?

My questions table is tblQA and my users are userID and questionID for the post. I want to run a query that helps me know how many active users are using the database every day.

Thanks so much!

SELECT userID
FROM tblQ
WHERE DATEDIFF(NOW(),postdate) < 7
GROUP BY userID
HAVING COUNT(DISTINCT DATE(postdate)) = 7