CREATE TABLE IF NOT EXISTS purchase_prices (
    id INT AUTO_INCREMENT PRIMARY KEY,
    article_id INT NOT NULL,
    supplier_id INT NOT NULL,
    price DECIMAL(10,2) NOT NULL,
    quantity DECIMAL(10,2) NOT NULL,
    purchase_date DATE NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (article_id) REFERENCES articles(id),
    FOREIGN KEY (supplier_id) REFERENCES contacts(id)
);
