數據庫基礎

-- 創建數據庫
CREATE DATABASE book;

-- 刪除數據庫
DROP DATABASE book;

-- 創建表
CREATE TABLE t_student(
    id INT PRIMARY KEY AUTO_INCREMENT,-- 編號AUTO_INCREMENT自動編號
    studentName VARCHAR(20), -- 學生姓名
    sex VARCHAR(20),-- 性別
    birthday DATE,-- 生日
    tel VARCHAR(20) -- 最後一個數據不用，

);

-- 刪除表
DROP TABLE t_student;



-- 添加數據記錄
INSERT INTO t_student(studentName,sex,birthday,tel) 
    VALUES('張三','男','1989-10-10','18108026384');
INSERT INTO t_student(studentName,sex,birthday,tel) 
    VALUES('李四','男','1988-10-10','18108026584');
INSERT INTO t_student(studentName,sex,birthday,tel) 
    VALUES('王五','男','1991-10-10','18108026389');
INSERT INTO t_student(studentName,sex,birthday,tel) 
    VALUES('趙六','男','1989-10-10','18108926384');
-- 添加多條記錄
INSERT INTO t_student(studentName,sex,birthday,tel) 
    ('張三','男','1989-10-10','18108026384')，
    ('李四','男','1988-10-10','18108026584')，
    ('王五','男','1991-10-10','18108026389')，
    ('趙六','男','1989-10-10','18108926384')，
-- 刪除
DELETE FROM t_student WHERE studentName = '張三';
DELETE FROM t_student WHERE studentName LIKE '張%';
DELETE FROM t_student WHERE studentName LIKE '%三%';
DELETE FROM t_student WHERE sex LIKE '%男%';
DELETE FROM t_student WHERE id = 3;

-- 修改屬性
UPDATE t_student SET tel = '18108026384' WHERE studentName = '張三';

-- 修改多個屬性
UPDATE t_student SET tel = '110',birthday = '1989-01-11' WHERE studentName = '張三'; 

UPDATE t_student SET tel = '18108026384',sex = '男' WHERE studentName = '張三';


-- 查詢所有的特定屬性
SELECT *FROM t_student WHERE sex = '男';

-- 姓張的用戶
SELECT *FROM t_student WHERE studentName LIKE '%張%';

-- 兩個字的名字
SELECT * FROM t_student WHERE studentName LIKE '王_';

-- 電信用戶
SELECT *FROM t_student WHERE tel LIKE '18%';

-- 姓王的男性
SELECT *FROM t_student WHERE studentName LIKE '王%' AND sex = '男';

-- 90後
SELECT *FROM t_student WHERE birthday >= '1990-01-01' AND birthday <= '1999-12-31';

-- 所有移動用戶
SELECT *FROM t_student WHERE tel LIKE '13%' OR  tel LIKE '15%';

-- 查詢第三條到第五條記錄,
-- 2代表從第幾條開始，第一條是0
-- 3表示顯示幾條
SELECT *FROM t_student LIMIT 2,3;

-- 按年齡排序asc 升序，desc降序，默認升序
SELECT *FROM t_student ORDER BY birthday DESC;

-- 最小年齡
SELECT * FROM t_student ORDER BY birthday DESC LIMIT 0,1 ;

-- 添加沒有電話的學生
INSERT INTO t_student(studentName,sex,birthday) 
    VALUES ('呵呵','男','1898-4-4');

-- 查詢沒有電話的學生    
SELECT *FROM t_student WHERE tel IS NULL;

-- 查詢id我3.5.8的學生
SELECT *FROM t_student WHERE id IN (3,5,8);

-- 查詢所有性別,DISTINCT剔除重複記錄
SELECT DISTINCT sex FROM t_student;


-- 查詢表中所有的數據
SELECT * FROM t_student; -- *表示查詢所有的列