Mongo DB

Mongo DB

1. Download or do brew
2. It's kinda JSONy

Beginning

1. You can launch in the background or foreground:

Foreground:

mongod --config /usr/local/etc/mongod.conf

Background:

brew services start mongodb

2. Then launch it using mongo

What you can do:

• show dbs
• use DBNAME to create db
• db to whereami
• db.createUser({})

3. So let's create user

Users

db.createUser({
  user: "NAME",
  pwd: "PASS",
  role: ["readWrite" , "dbAdmin"]
});

4. and create collection...

Collections

• db.createCollection("COLLECTIONNAME") is like a table
• db.COLLECTION.insert({})
• db.COLLECTION.find()

and it is scalable!

Collection edit

Write

For example:

db.customers.insert([{first_name: "Regina", last_name: "Valetova"},{first_name: "Ivan", last_name: "Dorow", age: 13}])

Or to make prettier: db.COLLECTION.find().pretty();

Edit

5. In order to Match and update:

For example:

db.customers.update({first_name: "Regina"},{first_name: "Regina", last_name: "Waletou", age: 14})

$set

However, if we want to change just one cell, we can do:

db.customers.update({first_name:"Regina"},{$set:{hasSpouse: true}})

$inc

db.customers.update({last_name: "Valetova"},{$inc:{age:1}})

$set

Deleting an option:

db.customers.update({first_name:"Regina"},{$unset:{hasSpouse: true}})

upsert

If we want to match something and edit, but it isn't there, it won't make anything, yet we can create new object, in case none was found:

db.customers.update({first_name:"Regina"},{$set:{hasSpouse: true},{upsert: true}})

rename

if we want to rename the key:

db.customers.update({first_name: "Brad"},{$rename: {"age": "old"}})

remove

db.customers.remove({first_name: "Darth"})

$or

db.customers.find({$or:[{first_name: "Luke"},{age: 22}]})

$gt $lt

db.customers.find({age:{$gt:14}})

inner objects

`db.customers.find(["adress.city": "Boston"]);

Sorting

db.cutomers.find().sort({last_name: 1});

Would sort alphabetically by last name, or -1 if reversed

Count

db.customers.find().count()

db.customers.find().limit(4)

forEach

db.customers.find().forEach(function(doc){print("Customer Name: " + doc.first_name)});