From 5105485f39cf2d6d107abc71d5c86a83ee58426f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=99=88=E6=98=8A=E7=AB=A5?=
 <10033735+Harshreich@user.noreply.gitee.com>
Date: Thu, 15 Sep 2022 15:45:04 +0000
Subject: [PATCH] =?UTF-8?q?=E9=99=88=E6=98=8A=E7=AB=A510?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: 陈昊童 <10033735+Harshreich@user.noreply.gitee.com>
---
 .../\344\275\234\344\270\232/22.9.15.sql"     | 30 +++++++++
 ...73\351\224\256\345\244\226\351\224\256.md" | 65 +++++++++++++++++++
 2 files changed, 95 insertions(+)
 create mode 100644 "\351\231\210\346\230\212\347\253\245/\344\275\234\344\270\232/22.9.15.sql"
 create mode 100644 "\351\231\210\346\230\212\347\253\245/\347\254\224\350\256\260/22.9.15\347\272\246\346\235\237\344\270\273\351\224\256\345\244\226\351\224\256.md"

diff --git "a/\351\231\210\346\230\212\347\253\245/\344\275\234\344\270\232/22.9.15.sql" "b/\351\231\210\346\230\212\347\253\245/\344\275\234\344\270\232/22.9.15.sql"
new file mode 100644
index 0000000..3b6283d
--- /dev/null
+++ "b/\351\231\210\346\230\212\347\253\245/\344\275\234\344\270\232/22.9.15.sql"
@@ -0,0 +1,30 @@
+create database DBTEST;
+create table sectioninfo(
+sectionID int primary key identity(0,1),
+sectionName varchar(10) not null 
+)
+;
+create table userinfo(
+userNo int primary key identity(0,1),
+userName varchar(10) not null unique check(len(userName)>4),
+userSex varchar(2) not null check(userSex=''or userSex='Ů'),
+userAge int not null check(userAge between 1 and 100),
+userAddress  varchar(50) default(''),
+userSection  int references sectioninfo(sectionID)
+)
+;
+create table workinfo(
+workId int primary key identity(0,1),
+userId  int references userinfo(userNo) not null ,
+workTime datetime not null,
+workDescription  varchar(40) not null check(workDescription in('ٵ','','','','¼'))
+)
+;
+select * from sectioninfo;
+select * from userinfo;
+select * from workinfo;
+insert into sectioninfo values('');
+insert into userinfo values('3323','','1','','1');
+insert into workinfo values('3','2022-3-3','');
+insert into workinfo values('3','2022-3-3','');
+insert into workinfo values('3','2022-3-3','¼');
diff --git "a/\351\231\210\346\230\212\347\253\245/\347\254\224\350\256\260/22.9.15\347\272\246\346\235\237\344\270\273\351\224\256\345\244\226\351\224\256.md" "b/\351\231\210\346\230\212\347\253\245/\347\254\224\350\256\260/22.9.15\347\272\246\346\235\237\344\270\273\351\224\256\345\244\226\351\224\256.md"
new file mode 100644
index 0000000..4773c94
--- /dev/null
+++ "b/\351\231\210\346\230\212\347\253\245/\347\254\224\350\256\260/22.9.15\347\272\246\346\235\237\344\270\273\351\224\256\345\244\226\351\224\256.md"
@@ -0,0 +1,65 @@
+--关系型数据库:SQL server, Mysql, Oracle 
+--创建数据库：create database 数据库名
+--database:数据库
+
+if exists (select * from sys.databases where name='DBTEST')
+ drop database DBTEST
+
+ create database DBTEST
+
+ --使用数据库
+ use dbtest
+
+ --创建班级表
+ create table ClassInfo(
+	ClassId int primary key identity(1,1),
+	ClassName varchar(20)
+ );
+
+ --插入数据： insert [into] 表名(字段名) values(值)
+ insert into ClassInfo( ClassName) values('软件1班');
+ 
+ insert ClassInfo values('软件2班')
+
+ select * from ClassInfo
+
+ --创建数据表
+ create table StuInfo(
+	stuId int primary key identity(1001,1),  --学生ID
+	--添加一个检查约束，判断用户插入/新增的数据，性别字段是不是男或者女
+	--default:默认约束
+	--check
+	stugender varchar(2) not null default('男') check(stugender='男' or stugender='女'),   --学生性别
+	stuphone char(11) check(len(stuphone)=11) unique,
+	--创建班级外键
+	--ClassID int references ClassInfo(ClassID)
+	ClassID int
+	
+ );
+
+
+ --增加外键
+ --修改表结构 表名 add constraint 约束名 foreign key(要引用的字段) references 主键表(字段)
+ Alter table StuInfo add constraint FK_StuInfo_ClassId foreign key(ClassID) references ClassInfo(ClassID)
+
+
+ --新增姓名列
+ alter table StuInfo add stuName varchar(20)
+
+ select * from StuInfo;
+
+ --删除表:drop table 表名
+ drop table StuInfo
+
+
+ --非空
+
+ --约束，自增(标识列)
+
+ --外键
+ --主键：默认唯一列
+ --默认
+ --唯一：
+ --check检查:
+
+ --插入数据：insert into
\ No newline at end of file
-- 
Gitee