Updating Documents

Updating documents in MongoDB with PHP involves using the updateOne or updateMany methods from the MongoDB PHP library. These methods allow for precise updates, whether targeting a single document or multiple ones.

Before performing updates, establish a connection to MongoDB. Use the MongoDB client to interact with the database.

Updating a Single Document

The updateOne method is ideal for updating a single document. Specify a filter to identify the document and an update array to define changes.

$filter = ['username' => 'john_doe'];
$update = ['$set' => ['email' => 'john.doe@example.com']];

$result = $collection->updateOne($filter, $update);

echo $result->getModifiedCount() . " document updated.";

The filter targets documents with a specific username, and the $set operator modifies the email field.

Let's move on to the following section on how to update multiple documents at once.

Updating Multiple Documents

When multiple documents need updates, use updateMany. This method applies changes to all matching documents.

$filter = ['status' => 'inactive'];
$update = ['$set' => ['status' => 'active']];

$result = $collection->updateMany($filter, $update);

echo $result->getModifiedCount() . " documents updated.";

This example updates the status field for all documents marked as inactive. Let's see how we can do that using additional operators in the section below.

Using Additional Update Operators

MongoDB supports various update operators, such as $inc, $push, and $unset. These operators enable advanced update operations.

Incrementing a value

$filter = ['views' => ['$exists' => true]];
$update = ['$inc' => ['views' => 1]];

$result = $collection->updateOne($filter, $update);
echo $result->getModifiedCount() . " document updated.";

It increments the views field for a document in a MongoDB collection. The $filter checks if the views field exists using the $exists operator. The $update uses the $inc operator to increase the views value by 1. The updateOne method applies the update to the first matching document, and the getModifiedCount() method returns the number of documents modified, which is then displayed.

Adding elements to an array

$filter = ['username' => 'john_doe'];
$update = ['$push' => ['tags' => 'new_tag']];

$result = $collection->updateOne($filter, $update);
echo $result->getModifiedCount() . " document updated.";

It adds a new value to the tags array field in a MongoDB document. The $filter targets a document where the username is john_doe. The $update uses the $push operator to append 'new_tag' to the tags array. The updateOne method applies the update to the first matching document, and the getModifiedCount() method outputs the number of documents modified.

Let's summarize it.

Wrapping Up

Updating documents in MongoDB allows you to modify data in a simple way, So if you need to adjust single fields or update multiple records at once. It is an important for managing dynamic databases.

Here is a quick recap of what we covered:

Thank you for reading this guide, and as always, happy coding!