In this article you will learn to find accounts in a MySQL server and remote unnecessary user accounts.

View Current Users

Connect to the existing MySQL server using administrative privileged account.

mysql -u root -p 

Next, list all the available user account in MySQL server. Default database named “mysql” contains system related details including user account under “user” table.

SELECT User,Host FROM mysql.user; 

List out the account with hostname to delete or all unused accounts no longer required.

Drop/Delete MySQL User

Use DROP USER statement is used to delete one or more accounts from MySQL. It also removes privilege rows for the account from all grant tables. You must have specified username along with hostname as per showing in above screenshot.

For example, to remove user “dummy” with host “localhost”, execute below query:

DROP USER 'dummy'@'localhost';

The above command drop only those user from MySQL maches both username and hostname.

Let’s use another example to delete user “myuser” with hostname “%”, execute below query.

DROP USER 'myuser'@'%';

That’s it. Repeat the same command to remove more accounts no longer required.

Conclusion

This tutorial describes you to how to remove user accounts from MySQL database server.

The post How to Delete A MySQL User Account appeared first on TecAdmin.

1. Create Database in MongoDB

It’s strange to listen but true that MongoDB doesn’t provide any command to create databases. Then the question is how would we create database ?. The answer is – We don’t create database in MongoDB, we just need to use database with your preferred name and need to save a single record in database to create it.

List Databases – First check the current databases in our system.

# mongo
> show dbs;

admin  (empty)
local  0.078GB
test   0.078GB

Use New Database –
Now if we want to create database with name exampledb. Just run following command and save a single record in database. After saving your first example, you will see that new database has been created.

> use exampledb;
> s = { Name : "TecAdmin.net" }
> db.testData.insert( s );

List Databases –
Now if you list the databases, you will see the new database will be their with name exampledb.

> show dbs;

admin  (empty)
local  0.078GB
exampledb   0.078GB
test   0.078GB

2. Drop Database in MongoDB

MongoDB provides dropDatabase() command to drop currently used database with their associated data files. Before deleting make sure what database are you selected using db command.

> db

exampledb

Now if you execute dropDatabase() command. It will remove exampledb database.

> db.dropDatabase();

{ "dropped" : "exampledb", "ok" : 1 }

To delete MongoDB database from Linux command line or Shell Script – Use following command from

# mongo exampledb --eval "db.dropDatabase()"

References:
1. http://docs.mongodb.org/manual/tutorial/getting-started/
2. http://docs.mongodb.org/manual/reference/command/dropDatabase/

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