diff --git "a/\347\275\227\345\220\257\346\201\222/.keep" "b/\347\275\227\345\220\257\346\201\222/.keep" new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git "a/\347\275\227\345\220\257\346\201\222/\347\275\227\345\220\257\346\201\222/\344\275\234\344\270\232/2022-9-16 \344\275\234\344\270\232.sql" "b/\347\275\227\345\220\257\346\201\222/\347\275\227\345\220\257\346\201\222/\344\275\234\344\270\232/2022-9-16 \344\275\234\344\270\232.sql" new file mode 100644 index 0000000000000000000000000000000000000000..e075fac7bf2445923d839c6864054999f1a820bf --- /dev/null +++ "b/\347\275\227\345\220\257\346\201\222/\347\275\227\345\220\257\346\201\222/\344\275\234\344\270\232/2022-9-16 \344\275\234\344\270\232.sql" @@ -0,0 +1,54 @@ + +CREATE DATABASE DBTEST; +USE dbtest +if exists (select * from sys.databases where name='sectionInfo') +drop table sectionInfo + +create table sectionInfo( + sectionID int primary key identity(1,1), + sectionName varchar(10) not null, +); + + + insert into sectionInfo(sectionName) values('超人部'); + insert into sectionInfo(sectionName) values('蜘蛛部'); + insert into sectionInfo(sectionName) values('钢铁部'); + insert into sectionInfo(sectionName) values('神奇部'); + insert into sectionInfo(sectionName) values('巨人部'); + + + +create table userInfo( + userNo int identity(0,1) primary key not null, + userName varchar(10)UNIQUE not null check(len(userName) >4), + userSex varchar(2) not null check(userSex='男' or userSex='女'), + userAge int not null check(1<=userAge or userAge<=100), + userAddress varchar(50) default('湖北'), + userSection int references sectionInfo(sectionID) +); + + +insert into userInfo(userName,userSex,userAge,userAddress,userSection) values +('王八','男','25','火星','0'), +('坤子','男','36','水星','1'), +('鸡子','女','9','土星','2'), +('凡凡','男','15','地球','3'), +('峰峰','男','65','月球','4'); + +create table workInfo( + workId int primary key identity(1,1) not null, + userId int references userInfo(userNo) not null, + workTime date not null , + workDescription varchar(40) not null check(workDescription='迟到' or workDescription='早退'or workDescription='病假'or workDescription='事假'), +); + + insert into workInfo(userId,workTime,workDescription) values ('1','2021-9-15','迟到'); + insert into workInfo(userId,workTime,workDescription) values ('3','2021-6-5','早退'); + insert into workInfo(userId,workTime,workDescription) values ('5','2021-6-25','早退'); + insert into workInfo(userId,workTime,workDescription) values ('2','2021-6-30','迟到'); + insert into workInfo(userId,workTime,workDescription) values ('4','2021-7-25','病假'); + + + select * from sectionInfo; + select * from userInfo; + select * from workInfo; diff --git "a/\347\275\227\345\220\257\346\201\222/\347\275\227\345\220\257\346\201\222/\347\254\224\350\256\260/2022-09-15-\347\254\224\350\256\260.sql" "b/\347\275\227\345\220\257\346\201\222/\347\275\227\345\220\257\346\201\222/\347\254\224\350\256\260/2022-09-15-\347\254\224\350\256\260.sql" new file mode 100644 index 0000000000000000000000000000000000000000..526c95eeea0bdab3b3c359d4b5cc675ed24bdedc --- /dev/null +++ "b/\347\275\227\345\220\257\346\201\222/\347\275\227\345\220\257\346\201\222/\347\254\224\350\256\260/2022-09-15-\347\254\224\350\256\260.sql" @@ -0,0 +1,78 @@ +--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) + + + + --如果没给出列名,默认是按照顺序一个个添加 + --insert StuInfo values('女',13888888888) + + --insert StuInfo(stuphone) values(15888888888) + + + + select * from StuInfo; + + --字符串:char(5),varchar(5),nvarchar(5)之间区别是什么 + + + + --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