@NavinoEvans and @Eugene233, on creating a reporting page where admins can view active user stats for different campaigns and time periods. I think of using a task scheduler like Celery to periodically run the query and store the results in a reporting table for faster access. I would like to know if a good idea.
Also, an upcomming feature of visualizing active user trends over time could be envisage.

@Sebastian_Berlin-WMSE, @Eugene233, @NavinoEvans. I wish to suggest on checking if the same image (with the same page_id and campaign_id) exists. Then fetches all images in the given category and if, depth is more than 0, its subcategories filter out pages that do not match for images. What are your reviews?

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