mysql join之后重复列名

SELECT orders.order_id, customers.customer_name
FROM orders
JOIN customers ON orders.customer_id = customers.customer_id;

SELECT orders.order_id AS order_id_orders, customers.customer_name AS customer_name_customers
FROM orders
JOIN customers ON orders.customer_id = customers.customer_id;

SELECT orders.order_id, customers.customer_name
FROM orders
JOIN customers ON orders.customer_id = customers.customer_id;

SELECT orders.order_id, customers.customer_name
FROM orders
JOIN customers ON orders.customer_id = customers.customer_id;

-- 创建示例表
CREATE TABLE employees (
    employee_id INT PRIMARY KEY,
    employee_name VARCHAR(100),
    department_id INT
);

CREATE TABLE departments (
    department_id INT PRIMARY KEY,
    department_name VARCHAR(100)
);

-- 插入示例数据
INSERT INTO employees (employee_id, employee_name, department_id) VALUES
(1, 'Alice', 1),
(2, 'Bob', 2),
(3, 'Charlie', 1);

INSERT INTO departments (department_id, department_name) VALUES
(1, 'HR'),
(2, 'Engineering');

-- 使用别名解决重复列名问题
SELECT e.employee_id AS employee_id_employees, e.employee_name, d.department_id AS department_id_departments, d.department_name
FROM employees e
JOIN departments d ON e.department_id = d.department_id;