mysql的行列转换sql

CREATE TABLE sales (
    id INT AUTO_INCREMENT PRIMARY KEY,
    product VARCHAR(50),
    month VARCHAR(10),
    amount DECIMAL(10, 2)
);

INSERT INTO sales (product, month, amount) VALUES
('ProductA', 'Jan', 100),
('ProductA', 'Feb', 150),
('ProductB', 'Jan', 200),
('ProductB', 'Feb', 250);

SELECT product,
       SUM(CASE WHEN month = 'Jan' THEN amount ELSE 0 END) AS Jan,
       SUM(CASE WHEN month = 'Feb' THEN amount ELSE 0 END) AS Feb
FROM sales
GROUP BY product;

CREATE TABLE products (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(50),
    attributes JSON
);

INSERT INTO products (name, attributes) VALUES
('ProductA', '{"color": "red", "size": "large"}'),
('ProductB', '{"color": "blue", "size": "small"}');

SELECT name,
       JSON_UNQUOTE(JSON_EXTRACT(attributes, '$.color')) AS color,
       JSON_UNQUOTE(JSON_EXTRACT(attributes, '$.size')) AS size
FROM products;