Les combinateurs Array et If peuvent être appliqués à la fonction uniq
pour compter le nombre de valeurs uniques dans des tableaux pour les lignes où la
condition est true, à l’aide de la fonction de combinateur d’agrégation uniqArrayIf.
-If et -Array peuvent être combinés. Cependant, Array doit venir en premier, puis If.
arrayJoin.
Compter les produits uniques consultés par type de segment et niveau d’engagement
CREATE TABLE user_shopping_sessions
(
session_date Date,
user_segment String,
viewed_products Array(String),
session_duration_minutes Int32
) ENGINE = Memory;
INSERT INTO user_shopping_sessions VALUES
('2024-01-01', 'new_customer', ['smartphone_x', 'headphones_y', 'smartphone_x'], 12),
('2024-01-01', 'returning', ['laptop_z', 'smartphone_x', 'tablet_a'], 25),
('2024-01-01', 'new_customer', ['smartwatch_b', 'headphones_y', 'fitness_tracker'], 8),
('2024-01-02', 'returning', ['laptop_z', 'external_drive', 'laptop_z'], 30),
('2024-01-02', 'new_customer', ['tablet_a', 'keyboard_c', 'tablet_a'], 15),
('2024-01-02', 'premium', ['smartphone_x', 'smartwatch_b', 'headphones_y'], 22);
-- Count unique products viewed by segment type and engagement level
SELECT
session_date,
-- Count unique products viewed in long sessions by new customers
uniqArrayIf(viewed_products, user_segment = 'new_customer' AND session_duration_minutes > 10) AS new_customer_engaged_products,
-- Count unique products viewed by returning customers
uniqArrayIf(viewed_products, user_segment = 'returning') AS returning_customer_products,
-- Count unique products viewed across all sessions
uniqArray(viewed_products) AS total_unique_products
FROM user_shopping_sessions
GROUP BY session_date
ORDER BY session_date
FORMAT Vertical;
Row 1:
──────
session_date: 2024-01-01
new_customer⋯ed_products: 2
returning_customer_products: 3
total_unique_products: 6
Row 2:
──────
session_date: 2024-01-02
new_customer⋯ed_products: 2
returning_customer_products: 2
total_unique_products: 7
