Basic MongoDB Terminal Commands
Posted on July 17, 2015 in MongoDB by Matt Jennings
After installing MongoDB, below are some basic terminal commands.
Start MongoDB
Open a terminal window, become a root user, and do:
mongod
View MongoDB Database(s)
Open ANOTHER terminal window, become a rooter user, and do:
mongo
Then to show MongoDB database(s) do:
show dbs
*NOTE: Database that are created and do NOT have collection(s) (analogous to tables in MySQL) will NOT appear when you do show dbs. After you add collection(s) they will appear when you do show dbs.
Create and Switch to a Database Named test_app
use test_app
Switch to a Database that Has Already Been Created Named matt_db
use matt_db
Show the Current Database You Are In
db
Delete a Database You are Currently In
db.dropDatabase()
Create a Collection in a Database
A MongoDB collection is analogous to a MySQL table, and to create one named users in the current table you are in do:
db.createCollection("users");
Insert a Document into a Collection
A new MongoDB document can be inserted into a collection. This is analogous to inserting a new MySQL row into a table. To insert a new document into a users collection do the command below, which inserts data in a Binary JSON (BSON) format.
BSON extends JSON by including additional data types to be more efficient for encoding and decoding within different languages. Do:
db.users.insert({name: "Matt"})
Show Collects in the Database Your Are In
show collections
Delete a Collection named comments
db.comments.drop()
Clear Screen
cls
Show All Documents in a ninjas Collection
db.ninjas.find()
In an Easier-To-Read-Format, Show All Documents in a ninjas Collection
db.ninjas.find().pretty()
Find One Document for { name: "Trey" }
db.ninjas.find( {name: "Trey"} ).pretty()
Example of Querying by an ID that MongoDB Creates Automatically for Every Document
db.ninjas.find( {_id: ObjectId("55a96d10816d4bd07b2f1503")} );
Remove a {name: "Trey"} Document
db.ninjas.remove( {name: "Trey"} )
If Two Documents Have the Same Property Name and Values of {name: "Carlos"}, Only Remove one of Them
db.ninjas.remove( {name: "Carlos"}, true )
Update a Document with a { "name" : "Tiger Woods" } Property using the $set Operator
db.ninjas.update( {name: "Tiger Woods"}, {$set: {location: "Mountain View"}} )