mysql建表并添加说明

CREATE TABLE `employees` (
    `id` INT(11) NOT NULL AUTO_INCREMENT COMMENT '员工ID',
    `first_name` VARCHAR(45) NOT NULL COMMENT '名字',
    `last_name` VARCHAR(45) NOT NULL COMMENT '姓氏',
    `email` VARCHAR(100) NOT NULL UNIQUE COMMENT '电子邮件',
    `phone_number` VARCHAR(20) COMMENT '电话号码',
    `hire_date` DATE NOT NULL COMMENT '雇佣日期',
    `job_id` INT(11) NOT NULL COMMENT '职位ID',
    `salary` DECIMAL(8, 2) NOT NULL COMMENT '薪水',
    `commission_pct` DECIMAL(2, 2) COMMENT '佣金百分比',
    `manager_id` INT(11) COMMENT '经理ID',
    `department_id` INT(11) NOT NULL COMMENT '部门ID',
    PRIMARY KEY (`id`),
    KEY `fk_job_id` (`job_id`),
    KEY `fk_department_id` (`department_id`),
    CONSTRAINT `fk_job_id` FOREIGN KEY (`job_id`) REFERENCES `jobs` (`job_id`),
    CONSTRAINT `fk_department_id` FOREIGN KEY (`department_id`) REFERENCES `departments` (`department_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='员工信息表';

CREATE TABLE `employee` (
    `employee`_id` INT(11) NOT NULL AUTO_INCREMENT COMMENT '员工ID',
    `first_name` VARCHAR(45) NOT NULL COMMENT '名字',
    PRIMARY KEY (`employee_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='员工表';