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104 lines
3.3 KiB
HTML
104 lines
3.3 KiB
HTML
<p>Table: <code>Movies</code></p>
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<pre>
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+---------------+---------+
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| Column Name | Type |
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+---------------+---------+
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| movie_id | int |
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| title | varchar |
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+---------------+---------+
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movie_id is the primary key (column with unique values) for this table.
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title is the name of the movie.
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</pre>
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<p> </p>
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<p>Table: <code>Users</code></p>
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<pre>
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+---------------+---------+
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| Column Name | Type |
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+---------------+---------+
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| user_id | int |
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| name | varchar |
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+---------------+---------+
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user_id is the primary key (column with unique values) for this table.
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</pre>
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<p> </p>
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<p>Table: <code>MovieRating</code></p>
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<pre>
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+---------------+---------+
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| Column Name | Type |
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+---------------+---------+
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| movie_id | int |
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| user_id | int |
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| rating | int |
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| created_at | date |
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+---------------+---------+
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(movie_id, user_id) is the primary key (column with unique values) for this table.
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This table contains the rating of a movie by a user in their review.
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created_at is the user's review date.
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</pre>
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<p> </p>
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<p>Write a solution to:</p>
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<ul>
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<li>Find the name of the user who has rated the greatest number of movies. In case of a tie, return the lexicographically smaller user name.</li>
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<li>Find the movie name with the <strong>highest average</strong> rating in <code>February 2020</code>. In case of a tie, return the lexicographically smaller movie name.</li>
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</ul>
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<p>The result format is in the following example.</p>
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<p> </p>
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<p><strong class="example">Example 1:</strong></p>
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<pre>
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<strong>Input:</strong>
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Movies table:
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+-------------+--------------+
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| movie_id | title |
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+-------------+--------------+
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| 1 | Avengers |
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| 2 | Frozen 2 |
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| 3 | Joker |
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+-------------+--------------+
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Users table:
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+-------------+--------------+
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| user_id | name |
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+-------------+--------------+
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| 1 | Daniel |
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| 2 | Monica |
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| 3 | Maria |
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| 4 | James |
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+-------------+--------------+
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MovieRating table:
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+-------------+--------------+--------------+-------------+
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| movie_id | user_id | rating | created_at |
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+-------------+--------------+--------------+-------------+
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| 1 | 1 | 3 | 2020-01-12 |
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| 1 | 2 | 4 | 2020-02-11 |
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| 1 | 3 | 2 | 2020-02-12 |
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| 1 | 4 | 1 | 2020-01-01 |
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| 2 | 1 | 5 | 2020-02-17 |
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| 2 | 2 | 2 | 2020-02-01 |
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| 2 | 3 | 2 | 2020-03-01 |
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| 3 | 1 | 3 | 2020-02-22 |
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| 3 | 2 | 4 | 2020-02-25 |
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+-------------+--------------+--------------+-------------+
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<strong>Output:</strong>
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+--------------+
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| results |
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+--------------+
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| Daniel |
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| Frozen 2 |
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+--------------+
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<strong>Explanation:</strong>
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Daniel and Monica have rated 3 movies ("Avengers", "Frozen 2" and "Joker") but Daniel is smaller lexicographically.
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Frozen 2 and Joker have a rating average of 3.5 in February but Frozen 2 is smaller lexicographically.
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</pre>
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