How to install Mysql DataBase in linux

We  can check how to install mysql db in a linux machine

All files of mysql including DB are stored in /var/lib/mysql/ 

All configuration files are in /etc/my.cnf 

Install the package using yum

# yum install mysql mysql-server

And then start the mysql server

# service mysqld start

Here no root password set for the DB so any one can access the DB command

# mysql

For securing it set a root password for mysql

# mysqladmin -u root password 'password'

this will set a root password for mysql. If you want to update the mysql root password the do the following

# mysqladmin -u root -p'oldpassword' password 'newpassword'

Then to enter into mysql database run

# mysql -u root -p 

enter password:

or we can specify password after -p option but it will be visible to all

Now your  mysql data base is ready for operation with a default port of 3306.

Some basic mysql queries are 

To list all databases on the mysql sql server 

mysql> show databases;

Create a database on the sql server

mysql> create database [databasename];

To use a database

mysql> use dbname;

To create a table in the database

mysql> create table tablename(name varchar(20),dob int(20));

To see all the tables in the db

mysql> show tables;

To drop a particular table

mysql> drop table tablename;

To see the structure of a particular table

mysql> describe employee;

mysql> show columns from table-name; 

Show all data in a table

mysql> SELECT * FROM [table name];  

Granting  Database permission to a user, * will give all default permissions

mysql> grant usage on *.* to 'ctechz'@'localhost' identified by 'ctechz123'; 

Granting  particular permission to users,

mysql> grant select,insert,update,delete,create,drop on TestDb.* to 'ctechz'@'localhost' identified by  'ctechz123'; 

Creating a user to access db

mysql> create user ctechz identified by 'ctechz123';

To change the password for a user

mysql> set password for 'ctechz'@'localhost'=password('ctechz123'); 

 mysql> flush privileges;

Granting permission from any host

mysql> GRANT ALL PRIVILEGES ON *.* TO 'monty'@'%' WITH GRANT OPTION;

% means for all host
 

We can get the mysql history file from

  # vim .mysql_history  

from the above file we can get the commands that we run the mysql bd.

If you want to connect to a remote mysql server from your machine

#  mysql -uroot -p -h 192.168.1.245

Granting permission to access the database from a particular Ip

# grant all privileges on *.* to 'root'@'192.168.1.67' identified by 'mysql1';

# flush privileges;