Basic usage of MySQL database

Connect to the database remotely

mysql -u root -p　　#-u username
Write the ip address of the host you want to connect to after -h
Write the user name of the connection after -u
-p write password after carriage return
Enter the password after pressing Enter, the currently set password is toor

　　

database operations

Create database
 create database database name charset=utf8;

delete database
drop database database name;

switch database
use database name;

View the currently selected database
select database();

　　

table operations

View all tables in the current database
 show tables;

create table
create table table name (columns and types);

auto_increment means automatic growth

如： create table students( id int auto_increment primary key, sname varchar(10) not null );

Modify table
alter table table name add|change|drop column name type; 
such as: alter table students add birthday datetime;

delete table
drop table table name;

View table structure
desc table name;

change table name
rename table original table name to new table name;

View table creation statement
show create table '表名';

　　

data manipulation

Query
 select * from table name

Increase
Full column insert: insert into table name values(...)
Default insert: insert into tablename(column1,...) values(value1,...)
Insert multiple pieces of data at the same time: insert into table name values(...),(...)...;
or insert into tablename(column1,...) values(value1,...),(value1,...)...;
The primary key column is automatically increased, but it needs to occupy a place when inserting the whole column. Usually 0 is used. After the insertion is successful, the actual data shall prevail.

Revise
update table name set column 1=value 1,... where condition

delete
delete from table name where condition

Tombstone, the essence is to modify the operation update
alter table students add isdelete bit default 0;
If you need to delete then
update students isdelete=1 where ...;

　　

Backup and restore

Enter super administrator
 sudo -s

Enter the mysql library directory
cd / var / lib / mysql

Run the mysqldump command
mysqldump –uroot –p database name > ~/Desktop/backup file.sql;

Enter the mysql password as prompted

Data Recovery
Connect to mysqk and create a database

To exit the connection, execute the following command

mysql -uroot -p database name < ~/Desktop/backup file.sql
Enter the mysql password as prompted