MongoDB Update – Geek Slack

MongoDB Tutorial

Introduction

Learn how to update documents in a MongoDB collection using the mongosh shell interface.

Connecting to MongoDB

Before updating documents, ensure you are connected to your MongoDB server:

Example: Connecting to MongoDB

mongosh

This command starts the mongosh shell and connects to the default MongoDB server running locally.

Switching to a Database

Switch to the database where your collection resides using the use command:

Example: Switching to a Database

use mydatabase

This command switches to the “mydatabase” database. Replace mydatabase with your database name.

Updating Documents

To update documents in a MongoDB collection, use the updateOne or updateMany methods:

Example: Updating a Single Document

db.mycollection.updateOne(
    { name: "John Doe" },
    { $set: { status: "inactive" } }
)

This command updates a single document in the mycollection collection where the name field equals “John Doe”, setting the status field to “inactive”.

Example: Updating Multiple Documents

db.mycollection.updateMany(
    { status: "active" },
    { $set: { status: "inactive" } }
)

This command updates multiple documents in the mycollection collection where the status field equals “active”, setting the status field to “inactive”.

Updating with Operators

Use update operators for more complex updates:

Example: Using Update Operators

db.mycollection.updateOne(
    { name: "Alice Smith" },
    { $inc: { age: 1 } }
)

This command increments the age field of the document where the name field equals “Alice Smith” by 1.

Verifying Updates

Verify that the documents have been updated by querying the collection:

Example: Verifying Updates

db.mycollection.find()

This command retrieves all documents from the mycollection collection. Check that your updates have taken effect.

Conclusion

Updating documents in a MongoDB collection using mongosh provides flexibility to modify existing data based on specific criteria. Experiment with different update methods and operators to suit your application’s needs.