Mongo DB Cheat Sheet

References

• Cheat Sheet
• mongoose - elegant mongodb object modeling for node.js

DB

use mydb
db.users.drop();

CRUDs

Insert

db.runCommand(
{
	insert: "users",
	documents: [ { _id: 2, user: "thoffmann", lastloggedin: null, logins: ["today", "yesterday"] } ]
})

Find

db.runCommand({
	find: "users"
})
db.users.find()
db.users.find({user: "thoffmann"})
db.users.find({logins: "today"})

db.users.find({
	$or: [
		{"name": "myuser"},
		{"name": {"$regex": "^Pe"}}
	]
})

// Only show Name
db.users.find({}, {name:true, _id:false})

Find Operators

All operator or keywords do start with $

**$gt / $gte** greater than
**$lt / $lte** lesser than
**$exists** does an attribute exist or not
**$regex** Regex
**$type** search by type

Update

db.runCommand({
	update: "users",
	updates: [{q: {user: "thoffmann"}, u: {lastloggedin: true}}]
})

Delete

db.runCommand({
	delete: "users",
	deletes: [ { q: { user: "thoffmann" }, limit: 1 } ]

})

Indexes

db.users.ensureIndex({name : 1})

Replica Sets

Sharding

Method of database partitioning