mysql分组取数据

-- 错误示例
SELECT product_name, category, SUM(sales) FROM sales_table GROUP BY category;

-- 正确示例
SELECT category, SUM(sales) AS total_sales FROM sales_table GROUP BY category;

-- 错误示例
SELECT category, SUM(sales) AS total_sales FROM sales_table GROUP BY category HAVING total_sales > 1000000;

-- 正确示例
SELECT category, SUM(sales) AS total_sales FROM sales_table GROUP BY category HAVING total_sales > 0;

SELECT category, SUM(sales) AS total_sales FROM sales_table GROUP BY category ORDER BY total_sales DESC;

CREATE TABLE sales_table (
    product_id INT,
    product_name VARCHAR(100),
    category VARCHAR(50),
    sales_amount DECIMAL(10, 2),
    sale_date DATE
);

SELECT category, SUM(sales_amount) AS total_sales
FROM sales_table
GROUP BY category
ORDER BY total_sales DESC;