Quick Access To Mongodb Commands Cheat Sheet

MongoDB is an NoSQL  document-oriented database program.  These are  my quick notes to  support MongoDB.

How to install MongoDB Enterprise on Red Hat Linux

--create a repo file and insert the text below

vi /etc/yum.repos.d/mongodb-enterprise.repo

[mongodb-enterprise]

name=MongoDB Enterprise Repository

baseurl=https://repo.mongodb.com/yum/redhat/$releasever/mongodb-enterprise/3.4/$basearch/

gpgcheck=1

enabled=1

gpgkey=https://www.mongodb.org/static/pgp/server-3.4.asc

--install the package

sudo yum install -y mongodb-enterprise

MongoDB version

db.version()

Log Into MongoDB

mongo - <my_username> -p <password> --authenticationDatabase <my_db>

Log into MongoDB Remotely via command line 

mongo -host <servername:port> -u <my_username> -p <password> --authenticationDatabase <my_db>

List all sessions 

use config
db.system.sessions.aggregate( [ { $listSessions: { allUsers: true } } ] )

Show all DBs

show dbs

Create the user Administrator 

Note:Once you've created the admin Users, you'll need to disconnect from the Mongo Shell & restart the Mongo Server

use admin
db.createUser(
  {
    user: "myUserAdmin",
    pwd: "abc123",
    roles: [ { role: "userAdminAnyDatabase", db: "admin" } ]
  }
)

Start the MongoDB service

sudo service mongod start

Start at the next system reboot

sudo chkconfig mongod on

To allow remote connections

Step1 : how to create a user in a db with readWrite 

db.createUser({

    user: 'robert',

    pwd: 'myM0ng0_pw',

    roles: [{ role: 'readWrite', db:'testdb'}]

})

Step 2 : Get the private address

/sbin/ifconfig | grep "inet addr" | awk -F: '{print $2}' | awk '{print $1}'

Step 3:edit mongo configuration file

--get private address from step 2 and add to bindip

vim /etc/mongod.conf

--change #security to:

security:

   authorization: enabled

Step 4: Then from the terminal you can run:

First you must have the mongo cli installed in your system (https://docs.mongodb.org/manual/installation/).

mongo someurl.mongodomain.com:45475/database_name -u username -p password

List all databases on a Mongo Server

show dbs

Create a database

To create a new database in MongoDB, first: select the database to use

    use my_new_database

To then check which database you're on 

   > db 

    my_new_database

You must then enter at least one document to create the db

> db.new_collection.insert({ some_key: "some_value" })

Show current Mongo db

db

db.getName()

Switch database used

use MY_DATABASE_NAME

List users 

db.getUsers()    or    show users

Create a role with specific access limited to a collection 

db.createRole({role: 'readRole', privileges: [{resource: {db:'mydb', collection:'mycollection'}, actions:['find']}], roles: [{role:'read',db:'mydb'}]})

db.createUser({
user: 'myuser',
pwd: 'my_pwd',
roles: [{ role: 'readRole', db:'mydb'}]
})

MongoDB Admin password change

Note:the user making the change must have Administrator privileges

db.changeUserPassword(‘adminusr’,’<new_password>’)

Drop a user

use testdb
db.dropUser("myUser1", {w: "majority", wtimeout: 5000})

Create a collection and insert on the fly

db.jacktest.insert ({ name: "Jack Vamvas", company: "dba-ninja.com" })

Create an index on a  collection

**This is an indepth topic that requires further development - but this is a sample example

db.jacktest.createIndex({"name.$**":1});

List indexes of a collection

db.jacktest.getIndexes();

List all collections in current database (extended information)

db.getCollectionInfos();

List all collections in current database (abbreviated)

db.getCollectionNames();

Read all rows in a collection

db.collection_name.find()

Get the current status of the replicaset

Note:returns the current status of the replicaset perspective from the server where command is executed

db.adminCommand( { replSetGetStatus: 1 } );

There are other NoSQL offers in other major DBMS such as SQL Server , and I'll post a feature comparison soon . Asking the question : What are your data needs?   is the first step in deciding the platform