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Change Events
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Change streams watch collections, databases, or deployments for changes.
When a change occurs on a watched resource, the change stream returns a change event notification document, with information on the operation and the changes it made.
Operation Types
Event | Description |
|---|---|
Occurs when a document is removed from the collection. | |
Occurs when a collection is dropped from a database. New in version 4.0.1. | |
Occurs when a database is dropped. New in version 4.0.1. | |
Occurs when an operation adds documents to a collection. | |
Occurs when an operation renders the change stream
invalid. | |
Occurs when a collection is renamed. New in version 4.0.1. | |
Occurs when an update operation removes a document from
a collection and replaces it with a new document. | |
Occurs when an operation updates a document in a collection. |
Resume Token
Each change event includes an _id field, which contain a document. This
document can serve as the resume token when
starting a change stream.