Notes from my presentation at the September MongoDB User Group.

1. For starters:
mongod - MongoDB Daemon
mongo - MongoDB Shell
From the shell:
db.help() - DB level help. Help is organized around the MongoDB hierarchy.
MongoDB is organized by databases which contain collections which contain
documents
show dbs - Display a list of databases
db.getCollectionNames() - Shows the collections in the current database
I ve downloaded a test dataset from Mongo for this talk at
https://raw.githubusercontent.com/mongodb/docs-assets/primer-
dataset/dataset.json Then, from a terminal command prompt:
mongoimport --db test --collection restaurants --drop --file
~/Documents/MongoDBUG/15.9.3/dataset.json
use test - Sets the test database as the current database. Note, if the
database doesn t exist, it will be created for you but no file footprint until
you put something in it.
show collections - same as the db.getCollecitonNames() above except show
collections is a list where the other returns an array.
db.restaurants.help() - Help for the restaurants collection we just created.
db.restaurants.count() - Number of documents in the restaurants collection.
db.restaurants.findOne()
db.restaurants.getIndexes() - Note changed in current version.
db.restaurants.ensureIndex({"name": 1}) - When a command expects parameters,
they are almost always a JSON document. Here I ve requested an index on the
name key, the 1 denotes ascending and -1 would have denoted descending. Note,
deprecated in the newest version, now its createIndex.
db.restaurants.find() - Finds matching documents. In this example no parameters
were passed in so it just finds things in no particular order.
db.restaurants.find({"name": "Glorious Food"})
db.restaurants.find({"name": "Glorious Food"}).pretty()
Query a subdocument
db.restaurants.find({"address.zipcode": "10021"})
db.restaurants.find({"address.zipcode": "10021"}).count()
db.restaurants.find({"address.zipcode": "10021"}).limit(3).pretty()
db.restaurants.find({"address.zipcode": "10021"}).sort({"name":
1}).limit(3).pretty()
Find restaurants that have received a score greater than 20:
db.restaurants.find({"grades.score": {$gt: 20}}).count()
Narrowing what you see with projections:
db.restaurants.find({"grades.score": {$gt: 20}}, {"name": 1, "cuisine": 1})
db.restaurants.distinct("cuisine") - Get a list of distant values for cuisine
db.restaurants.distinct("grades.grade")
db.restaurants.distinct("cuisine").sort("cuisine")
db.restaurants.count()
db.restuarants.insert({"address" : {"building" : "1361", "street" : "S Orange
Ave", "zipcode" : "32806"}, "cuisine" : "American ", "name" : "Wendy s",
"restaurant_id" : "89976993"})
db.restaurants.count()
Fix our fat finger
db.restuarants.drop()
db.restaurants.insert({"address" : {"building" : "1361", "street" : "S Orange

2. Ave", "zipcode" : "32806"}, "cuisine" : "American ", "name" : "Wendy s",
"restaurant_id" : "89976993"})
db.restaurants.remove({"address.zipcode": "32806"})