Count viewed article types

You are given two tables about article views. Table 1: `article_views` - `user_id` INT - `article_id` INT - `view_date` DATE — UTC calendar date of the view Table 2: `articles` - `article_id` INT - `article_type` STRING Relationship: - `article_views.article_id = articles.article_id` Assumptions: - Each row in `article_views` represents one article view event. - Dates are interpreted as UTC calendar dates. Write SQL for the following: 1. On `2019-01-01` UTC, compute the number of distinct article types viewed by each user. - Output columns: `user_id, num_article_types` 2. Build a histogram of the number of distinct article types viewed per user across all available dates. - For each distinct value of `num_article_types`, return how many users have that count. - Output columns: `num_article_types, num_users`