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mysql20170407代码实现

时间:2021-07-01 10:21:17 帮助过:10人阅读

test01 | | tree | | world | +--------------------+ 18 rows in set (0.00 sec) mysql> create database if not exists myschool; Query OK, 1 row affected (0.00 sec) mysql> show databases -> ; +--------------------+ | Database | +--------------------+ | information_schema | | bdqn | | mybatis | | myschool | | myschool2 | | mysql | | news | | performance_schema | | sakila | | school | | smbms | | smbmsdemo | | ssh01 | | t09 | | t12 | | test | | test01 | | tree | | world | +--------------------+ 19 rows in set (0.00 sec) mysql> create table if not exists `subject`() -> -> ; ERROR 1046 (3D000): No database selected mysql> create table if not exists `subject`(SubjectNo int(11),SubjectName vachar (50),ClassHour int(4),GradeID int(4))comment=课程数据表; ERROR 1046 (3D000): No database selected mysql> use myschool; Database changed mysql> create table if not exists `subject`(SubjectNo int(11),SubjectName vachar (50),ClassHour int(4),GradeID int(4))comment=课程数据表; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near vacha r(50),ClassHour int(4),GradeID int(4))comment=课程数据表‘‘ at line 1 mysql> create table if not exists `subject`(SubjectNo int(11),SubjectName vachar (50),ClassHour int(4),GradeID int(4))comment=课程数据表; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near vacha r(50),ClassHour int(4),GradeID int(4))comment=课程数据表‘‘ at line 1 mysql> create table if not exists `subject`(SubjectNo int(11),SubjectName varcha r(50),ClassHour int(4),GradeID int(4))comment=课程数据表; Query OK, 0 rows affected (2.20 sec) mysql> select * from subject -> ; Empty set (0.00 sec) mysql> select * from `subject`; Empty set (0.00 sec) mysql> insert into `subject` values(1,高等数学-1,120,1); Query OK, 1 row affected (0.14 sec) mysql> insert into `subject` values(2,高等数学-2,110,2); Query OK, 1 row affected (0.13 sec) mysql> insert into `subject` values(3,高等数学-3,100,3); Query OK, 1 row affected (0.13 sec) mysql> insert into `subject` values(4,高等数学-4,130,4); Query OK, 1 row affected (0.14 sec) mysql> insert into `subject` values(5,C语言-1,120,1); Query OK, 1 row affected (0.14 sec) mysql> insert into `subject` values(6,C语言-2,110,2); Query OK, 1 row affected (0.13 sec) mysql> select * from `subject`; +-----------+-------------+-----------+---------+ | SubjectNo | SubjectName | ClassHour | GradeID | +-----------+-------------+-----------+---------+ | 1 | 高等数学-1 | 120 | 1 | | 2 | 高等数学-2 | 110 | 2 | | 3 | 高等数学-3 | 100 | 3 | | 4 | 高等数学-4 | 130 | 4 | | 5 | C语言-1 | 120 | 1 | | 6 | C语言-2 | 110 | 2 | +-----------+-------------+-----------+---------+ 6 rows in set (0.00 sec) mysql> create table if not exists grade; ERROR 1113 (42000): A table must have at least 1 column mysql> create table if not exists grade(GradeID int(11) primary key,GradeName va rchar(50))comment=年级表; Query OK, 0 rows affected (2.22 sec) mysql> insert into grade values(1,大一); Query OK, 1 row affected (0.11 sec) mysql> insert into grade values(2,大二); Query OK, 1 row affected (0.13 sec) mysql> insert into grade values(3,大三); Query OK, 1 row affected (0.13 sec) mysql> insert into grade values(1,大四); ERROR 1062 (23000): Duplicate entry 1 for key PRIMARY mysql> insert into grade values(4,大四); Query OK, 1 row affected (0.13 sec) mysql> select * from grade; +---------+-----------+ | GradeID | GradeName | +---------+-----------+ | 1 | 大一 | | 2 | 大二 | | 3 | 大三 | | 4 | 大四 | +---------+-----------+ 4 rows in set (0.00 sec) mysql> create table if not exists student(StudentNo int(4) not null comment 学 号),,,Loginarchar(20) default null,StudentName varchar(20) default null comment 学ent 学生姓名,,,,, > ; > ; > kdjsf;a > ; > Bye C:\Users\Administrator>mysql -uroot -p Enter password: **** Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 9 Server version: 5.5.54-log MySQL Community Server (GPL) Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type help; or \h for help. Type \c to clear the current input statement. mysql> use myschool; Database changed mysql> create table if not exists student(StudentNo int(4) not null comment 学 号,LoginPwd varchar(20) default null,StudentName varchar(20) default null comme nt 学生姓名,Sex tinyint(1) default null comment 性别,取值0或1,GradeId int(1 1) default null comment 年级编号,Phone varchar(50) not null comment 联系电话 ,允许为空,即可选输入,Address varchar(255) not null comment 地址,允许为空, 即可选输入,BornDate datetime default null comment 出生时间,Email varchar(50) not null comment 邮箱账号,允许为空,即可选输入,IdentityCard varchar(18) defau lt null comment 身份证号)comment=学生类; Query OK, 0 rows affected (0.53 sec) mysql> select * from student; Empty set (0.02 sec) mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | bdqn | | mybatis | | myschool | | myschool2 | | mysql | | news | | performance_schema | | sakila | | school | | smbms | | smbmsdemo | | ssh01 | | t09 | | t12 | | test | | test01 | | tree | | world | +--------------------+ 19 rows in set (0.00 sec) mysql> use myschool; Database changed mysql> select * from student; Empty set (0.00 sec) mysql> show tables; +--------------------+ | Tables_in_myschool | +--------------------+ | grade | | student | | subject | +--------------------+ 3 rows in set (0.00 sec) mysql> select * from subject; +-----------+-------------+-----------+---------+ | SubjectNo | SubjectName | ClassHour | GradeID | +-----------+-------------+-----------+---------+ | 1 | 高等数学-1 | 120 | 1 | | 2 | 高等数学-2 | 110 | 2 | | 3 | 高等数学-3 | 100 | 3 | | 4 | 高等数学-4 | 130 | 4 | | 5 | C语言-1 | 120 | 1 | | 6 | C语言-2 | 110 | 2 | +-----------+-------------+-----------+---------+ 6 rows in set (0.00 sec) mysql> use myschool; Database changed mysql> show tables; +--------------------+ | Tables_in_myschool | +--------------------+ | grade | | student | | subject | +--------------------+ 3 rows in set (0.00 sec) mysql> drop subject if exists; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near subje ct if exists at line 1 mysql> drop table subject if exists; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near if ex ists at line 1 mysql> drop `subject` if exists; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near `subj ect` if exists at line 1 mysql> drop table if exists subject; Query OK, 0 rows affected (0.47 sec) mysql> show tables; +--------------------+ | Tables_in_myschool | +--------------------+ | grade | | student | +--------------------+ 2 rows in set (0.00 sec) mysql> create table if not exists subject(SubjectNo in(11) not null comment 课 程编号,SubjectName varchar(50) default null comment 课程名称,ClassHour int(4) default null comment 学时,GradeID int(4) default null comment 年级编号; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near in(11 ) not null comment 课程编号,SubjectName varchar(50) default null comm at line 1 mysql> create table if not exists subject(SubjectNo in(11) not null comment 课 程编号,SubjectName varchar(50) default null comment 课程名称,ClassHour int(4) default null comment 学时,GradeID int(4) default null comment 年级编号)engi ne=MyISAM,comment=课程名称表; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near in(11 ) not null comment 课程编号,SubjectName varchar(50) default null comm at line 1 mysql> create table if not exists subject(SubjectNo in(11) not null comment 课 程编号,SubjectName varchar(50) default null comment 课程名称,ClassHour int(4) default null comment 学时,GradeID int(4) default null comment 年级编号)engi ne=MyISAM comment=课程名称表; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near in(11 ) not null comment 课程编号,SubjectName varchar(50) default null comm at line 1 mysql> create table if not exists subject(SubjectNo in(11) not null comment 课 程编号,SubjectName varchar(50) default null comment 课程名称,ClassHour int(4) default null comment 学时,GradeID int(4) default null comment 年级编号)engi ne=MyISAM comment=课程名称表; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near in(11 ) not null comment 课程编号,SubjectName varchar(50) default null comm at line 1 mysql> create table if not exists subject(SubjectNo in(0t1) not null comment 课 程编号,SubjectName varchar(50) default null comment 课程名称,ClassHour int(4) default null comment 学时,GradeID int(4) default null comment 年级编号)engi ne=MyISAM comment=课程名称表; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near in(0t 1) not null comment 课程编号

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