mysql datetime设置默认值

CREATE TABLE table_name (
    column_name DATETIME DEFAULT default_value
);

CREATE TABLE orders (
    order_id INT AUTO_INCREMENT PRIMARY KEY,
    order_date DATETIME DEFAULT CURRENT_TIMESTAMP,
    customer_name VARCHAR(100)
);

INSERT INTO orders (customer_name) VALUES ('John Doe');

ALTER TABLE orders
MODIFY COLUMN order_date DATETIME DEFAULT CURRENT_TIMESTAMP;

DROP TABLE orders;
CREATE TABLE orders (
    order_id INT AUTO_INCREMENT PRIMARY KEY,
    order_date DATETIME DEFAULT CURRENT_TIMESTAMP,
    customer_name VARCHAR(100)
);

CREATE TABLE events (
    event_id INT AUTO_INCREMENT PRIMARY KEY,
    event_date DATETIME DEFAULT '2023-10-01 12:00:00',
    event_name VARCHAR(100)
);