Developers must-Mysql command

Developer necessary Mysql common commands, covering the data definition statements, data manipulation statements and control statements data, based Mysql5.7.

Data Definition Language (DDL)

Database operations

• Log database:

mysql -uroot -proot

• Create a database:

create database test

• View all databases:

show databases

• Select the database and use:

use test

• See all the data table:

show tables

• Delete the database:

drop database test

Operating Table

• Create a table:

create table emp(ename varchar(10),hiredate date,sal decimal(10,2),deptno int(2))  
create table dept(deptno int(2),deptname varchar(10))

• View the table definition:

desc emp

• View the table definition (detail):

show create table emp \G

• Delete the table:

drop table emp

• Modify table field:

alter table emp modify ename varchar(20)

• Adding table fields:

alter table emp add column age int(3)

• Delete the table fields:

alter table emp drop column age

• Fields renamed;

alter table emp change age age1 int(4)

• Modify the table name:

alter table emp rename emp1

Data manipulation statements (DML)

Insert Record

• Specify the name inserted:

insert into emp (ename,hiredate,sal,deptno) values ('zhangsan','2018-01-01','2000',1)

• Do not specify a name inserted:

insert into emp values ('lisi','2018-01-01','2000',1)

• Bulk insert data:

insert into dept values(1,'dept1'),(2,'dept2')

Modify records

update emp set sal='4000',deptno=2 where ename='zhangsan'

Delete Record

delete from emp where ename='zhangsan'

inquiry record

• Query all records:

select * from emp

• The query does not duplicate records:

select distinct deptno from emp

• Conditions inquiry:

select * from emp where deptno=1 and sal<3000

• Sort and restrictions:

select * from emp order by deptno desc limit 2

• Paging query (query from 0 to start recording 10):

select * from emp order by deptno desc limit 0,10

• Polymerization (the number of sectors is greater than the sector inquiry number 1):

select deptno,count(1) from emp group by deptno having count(1) > 1

• Join query:

select * from emp e left join dept d on e.deptno=d.deptno

• Subquery:

select * from emp where deptno in (select deptno from dept)

• Joint record:

select deptno from emp union select deptno from dept

Data control statements (DCL)

The relevant authority

• Granted operating authority (to grant test user test database select and insert permissions to all tables):

grant select,insert on test.* to 'test'@'localhost' identified by '123'

• View account permissions:

show grants for 'test'@'localhost'

• Recovery of operating authority:

revoke insert on test.* from 'test'@'localhost'

• All permissions granted to all databases:

grant all privileges on *.* to 'test'@'localhost'

• All permissions granted to all databases (including the grant):

grant all privileges on *.* to 'test'@'localhost' with grant option

• SUPER PROCESS FILE grant permission (the database system privileges can not be specified):

grant super,process,file on *.* to 'test'@'localhost'

• Only granted permission to log on:

grant usage on *.* to 'test'@'localhost'

Account Related

• Delete Account:

drop user 'test'@'localhost'

• Change the password:

set password = password('123')

• Administrators modified by someone else Password:

set password for 'test'@'localhost' = password('123')

other

Character Sets Related

• View character sets:

show variables like 'character%'

• Specify the character set when creating a database:

create database test2 character set utf8

The time zone

• View the current time zone (UTC unified time for the world, China is UTC + 8):

show variables like "%time_zone%"

• When you modify the global zone is GMT mysql, that we live East Area 8:

set global time_zone = '+8:00';

• Modify the current conversation area:

set time_zone = '+8:00'http://macro-oss.oss-cn-shenzhen.aliyuncs.com/mall/blog/refer_screen_50.png

• Effective immediately:

flush privileges