MongoDB Command Line Examples

This command shows all databases

show dbs

This command creates and activates the database for editing. If it is already created, it only activates for editing.

use wikiDB

This command creates a collection.

db.createCollection("articles")

In order to see all the collections under a specific database, use these 2 commands,

use wikiDB
show collections

If you have a collection named "articles", in order to insert set of objects, use the following command. In this example we only entered a single object.

db.articles.insertMany(
    [
        {
            title: "REST",
            content: "REST is short for REpresentational State Transfer. It is an architectural style for designing APIs."
        }
    ]
)

Alternatively, only one single object can be inserted into a collection like so,

db.articles.insertOne(
    {
        title: "REST",
        content: "REST is short for REpresentational State Transfer. It is an architectural style for designing APIs."
    }
)

updateOne only updates the data in the first object it finds, whereas updateMany updates the data in all objects that matches the criteria. Remember that you cannot update the "_id" of an object as "_id" is an immutable value.

db.articles.updateOne(
    {_id: ObjectId("617dfc7b8d9356506c768e0c")},
    {
        $set: {title: "Hi!", content: "How are you?"}
    }
)

Next command only removes the content of the collection.

db.articles.remove({})

This command completely deletes the collection.

db.articles.drop()

This is an example of inserting many object into an already existing collection.

db.articles.insertMany(
    [
        {
            "_id" : ObjectId("5c139771d79ac8eac11e754a"),
            "title" : "API",
            "content" : "API stands for Application Programming Interface. It is a set of subroutine definitions, communication protocols, and tools for building software. In general terms, it is a set of clearly defined methods of communication among various components. A good API makes it easier to develop a computer program by providing all the building blocks, which are then put together by the programmer."
        },

        {
            "_id" : ObjectId("5c1398aad79ac8eac11e7561"),
            "title" : "Bootstrap",
            "content" : "This is a framework developed by Twitter that contains pre-made front-end templates for web design"
        },

        {
            "_id" : ObjectId("5c1398ecd79ac8eac11e7567"),
            "title" : "DOM",
            "content" : "The Document Object Model is like an API for interacting with our HTML"
        }
    ]
)

Once you enter an info, in order to find it, use the following command.

db.articles.find()

Alternatively, you can create filtering for finding things in collection.

db.articles.find(
    {"title": "DOM"}
)

For example if the result seems unreadable, you can use pretty() method.

db.articles.find().pretty()

codecygen/033_MongoDB-Command-Line-Examples

MongoDB Command Line Examples