MongoDB: shell commands examples

Here are examples of common operations within the MongoDB Shell (mongosh):

1. Database Management:

show databases.

JavaScript

    show dbs

JavaScript

    use myDatabase

Show current database.

JavaScript

db

2. Collection Management:

Show collections in the current database.

JavaScript

    show collections

Create a new collection.

JavaScript

    db.createCollection("myCollection")

3. Data Manipulation (CRUD Operations):

Insert a single document.

JavaScript

    db.myCollection.insertOne({ name: "Alice", age: 30, city: "New York" })

Insert multiple documents.

JavaScript

    db.myCollection.insertMany([
        { name: "Bob", age: 25, city: "London" },
        { name: "Charlie", age: 35, city: "Paris" }
    ])

Find all documents in a collection.

JavaScript

    db.myCollection.find()

Find documents with specific criteria.

JavaScript

    db.myCollection.find({ age: { $gt: 28 } }) // Find documents where age is greater than 28

Find documents and project specific fields.

JavaScript

    db.myCollection.find({}, { name: 1, city: 1, _id: 0 }) // Include name and city, exclude _id

Update a single document.

JavaScript

    db.myCollection.updateOne({ name: "Alice" }, { $set: { age: 31 } })

Update multiple documents.

JavaScript

    db.myCollection.updateMany({ city: "London" }, { $set: { status: "active" } })

Delete a single document.

JavaScript

    db.myCollection.deleteOne({ name: "Bob" })

Delete multiple documents.

JavaScript

    db.myCollection.deleteMany({ status: "inactive" })

4. Utility Commands:

Clear the shell screen.

JavaScript

cls

exit the shell.

JavaScript

    exit