Mengelompokkan film

Pengambilan Keputusan Berbasis Data dengan SQL

Bart Baesens

Professor Data Science and Analytics

Aplikasi GROUP BY

Preferensi pelanggan per negara atau gender.
Popularitas film per genre atau tahun rilis.
Rata-rata harga film per genre.

Tabel: movies_selected

GROUP BY

SELECT genre
FROM movies_selected
GROUP BY genre;

| genre       |
|-------------|
| Drama       |
| Fantasy     |
| Sci-Fiction |
| Animation   |
| Romance     |

Rata-rata harga sewa

SELECT genre, 
       AVG(renting_price) AS avg_price
FROM movies_selected
GROUP BY genre;

| genre       | avg_price   |
|-------------|-------------|
| Drama       | 2.865       |
| Fantasy     | 2.69        |
| Sci-Fiction | 2.87        |
| Animation   | 2.923333333 |
| Romance     | 2.99        |

Tabel movies_selected

Tabel movies_selected terbagi

Rata-rata harga sewa dan jumlah film

SELECT genre, 
       AVG(renting_price) AS avg_price, 
       COUNT(*) AS number_movies
FROM movies_selected
GROUP BY genre

| genre       | avg_price     | number_movies |
|-------------|---------------|---------------|
| Drama       | 2.865         | 4             |
| Fantasy     | 2.69          | 3             |
| Sci-Fiction | 2.87          | 2             |
| Animation   | 2.923333333   | 3             |
| Romance     | 2.99          | 1             |

HAVING

SELECT genre, 
       AVG(renting_price) avg_price, 
       COUNT(*) number_movies
FROM movies
GROUP BY genre
HAVING COUNT(*) > 2;

| genre     | avg_price     | number_movies |
|-----------|---------------|---------------|
| Drama     | 2.865         | 4             |
| Fantasy   | 2.69          | 3             |
| Animation | 2.923333333   | 3             |

Ayo berlatih!

Pengambilan Keputusan Berbasis Data dengan SQL