Check again which databases are currently available

Recheck the current databases

First open cmd, enter net start mysqlStart the mysql service, and then enter mysql -hlocalhost -uroot -p Enter Log in to the database, and then you can enter the command.

There are many commands on the MySQL command line. To check which databases there are, we can use the show databases; command to check. Be careful not to forget the semicolon.

If you used the use mysql; statement before and want to query the current databases again, you still use the show databases; command. If you want to jump to Other databases can be switched using use test; , where test is the name of the database you want to switch.

Recommendation"mysql video tutorial"

In daily website maintenance and management, a lot of SQL statements are used, and proficient use has many benefits for website management. , especially when managing site groups, the following is a collection of commonly used MySQL commands on the command line. I hope it will be helpful to you.

18 commonly used commands under the MySQL command line

1. Display database

show databases

Display table

show tables;

2. Create user
Create root user with password 123

use mysql;
grant all on *.* to root@'%' identified by '123' with grant option;
commit;

3. Change password

grant all on *.* to xing@'localhost' identified by '123456' with grant option;
update user set password = password('newpwd') where user = 'xing' and host='localhost';
flush privileges;

4. Create database testdb:

create database testdb;

5 , Preventive creation of database:

create database if not testdb;

6. Creation of table:

use testdb;
create table table1(
username varchar(12),
password varchar(20));

7. Preventive creation of table aaa:

create table if not exists aaa(ss varchar(20));

8 , View table structure:

describe table1;

9. Insert data into table table1:

insert into table1(username,password) values
('leizhimin','lavasoft'),
('hellokitty','hahhahah');
commit;

10. Query table table1:

select * from table1;

11. Change data :

update table1 set password='hehe' where username='hellokitty';
commit;

12. Delete data:

delete from table1 where username='hellokitty';
commit;

13. Add a column to the table:

alter table table1 add column(
 sex varchar(2) comment '性别',
 age date not null comment '年龄'
);
commit;

14. Modify the table structure

Create a table table1 from the query:

create table tmp as
select * from table1;

15. Delete table table1:

drop table if exists table1;
drop table if exists tmp;

16. Back up database testdb

mysqldump -h 192.168.3.143 -u root -p pwd -x --default-character-set=gbk >C:\testdb.sql

17. Delete database testdb

drop database testdb;

18. Restoring the testdb database
First create the testdb database, and then use the following command to restore it locally

mysql -u root -pleizhimin testdb 
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