数据库练习

-- 新建数据库
CREATE DATABASE `school`;

-- 使用数据库
USE `SCHOOL`;

-- 创建字段
-- id:学生的ID
-- name:学生名称
-- nickname：学生昵称
-- sex：性别
-- in_time:入学时间

CREATE TABLE `student`(
	`id` INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
	`name` VARCHAR(20) NOT NULL,
	`nickname` VARCHAR(20) NULL,
	`sex` SMALLINT NOT NULL,
	`in_time` DATETIME NULL
);

-- 插入语句
INSERT INTO `student` VALUES(1,'张三','三哥','1',now())

-- 插入自增语句
INSERT INTO `student`(`name`,`sex`) VALUES
	('张三1','1'),
	('张三2','2'),
	('张三3','1')
;

-- 查询语句
SELECT `name`,`nickname` FROM `student`;
SELECT `id`,`name`,`nickname` FROM `student` WHERE `sex`='1';
SELECT `id`,`name`,`nickname` FROM `student` WHERE `sex`='1' ORDER BY `id` DESC;
SELECT `id`,`name`,`nickname` FROM `student` WHERE `sex`='1' ORDER BY `id` DESC LIMIT 0,2;

-- 修改语句
UPDATE `student` SET `sex`='2' WHERE `sex`='1';
UPDATE `student` SET `sex`='2',`nickname`='没有昵称';

-- 删除语句
DELETE FROM `student` WHERE `sex`='1';

pip install mysqlclient