PostgreSQL 中的条件分组依据（对相似项进行分组）

# PostgreSQL中的条件分组依据：对相似项进行分组

sql
CREATE TABLE products (
    id SERIAL PRIMARY KEY,
    name VARCHAR(100),
    category VARCHAR(50),
    price NUMERIC(10, 2)
);
INSERT INTO products (name, category, price) VALUES
    ('Laptop', 'Electronics', 1200.00),
    ('Smartphone', 'Electronics', 500.00),
    ('Coffee Maker', 'Appliances', 80.00),
    ('Toaster', 'Appliances', 40.00),
    ('Running Shoes', 'Apparel', 80.00),
    ('T-shirt', 'Apparel', 20.00);

sql
SELECT category, ARRAY_AGG(name) AS products_in_category
FROM products
GROUP BY category;

sql
SELECT
    CASE
        WHEN price < 50.00 THEN 'Low Range'
        WHEN price >= 50.00 AND price < 100.00 THEN 'Medium Range'
        ELSE 'High Range'
    END AS price_range,
    ARRAY_AGG(name) AS products_in_range
FROM products
GROUP BY price_range;