qq_42756072的博客

CREATE TABLE student( Num INT(10) PRIMARY KEY, Name VARCHAR(20) NOT NULL, Sex VARCHAR(4) NOT NULL, Birthday YEAR, Dept VARCHAR(20) NOT NULL, Address VARCHAR(50));CREATE TABLE score( Id INT(...

/*1.创建视图语法格式：CREATE [ALGORITHM = {UNDEFINED |MERGE | TEMPTABLE}]VIEW 视图名 [(视图列表)]AS 查询语句[WITH [CASCADED| LOCAL] CHECK OPTTION] */CREATE VIEW student_view1(SNAME,CNAME,SCORE) AS SELECT SN,CN...

CREATE TABLE S( SNO CHAR(6) PRIMARY KEY, SN VARCHAR(20) NOT NULL, AGE TINYINT UNSIGNED NOT NULL, DEPT VARCHAR(20) );INSERT S VALUES('S1','李立勇',20,'CS'), ('S2','刘蓝',23,'IS'),...

-- 创建省份表CREATE TABLE provinces(id TINYINT UNSIGNED AUTO_INCREMENT KEY,proName VARCHAR(10) NOT NULL UNIQUE);INSERT provinces(proName) VALUES('北京'),('上海'),('深圳');-- 管理员admin id username email ...

dep表+----+-----------------+-----------------------------+| id | depName | depDesc |+----+-----------------+-----------------------------+| 1 | 大数部 | 大学数学基础课...

-- 测试子查询-- 测试由IN引发的子查询SELECT * FROM empWHERE depId IN (SELECT id FROM dep);SELECT * FROM empWHERE depId NOT IN (SELECT id FROM dep);-- 由EXISTS 引发的子查询SELECT * FROM emp WHERE EXISTS (SELECT ...

--创建数据表，并添加数据CREATE TABLE user(id INT UNSIGNED AUTO_INCREMENT KEY,username VARCHAR(20) NOT NULL UNIQUE COMMENT '编号',age TINYINT UNSIGNED NOT NULL DEFAULT 18 COMMENT '年龄',sex ENUM('男','女','保密') ...

---在test数据库下创建数据表employee---CREATE TABLE employee( id SMALLINT, num CHAR(10), name VARCHAR(20), sex ENUM('男','女'), birthday DATE, address VARCHAR(50), salary FLOAT(8,2) );--查看test数据库下的所有表...