Manage Collections in Compass (original) (raw)

A collection is a grouping of MongoDBdocuments. Documents within a collection can have different fields. A collection is the equivalent of a table in a relational database system. A collection exists within a single database.

The Collections screen lists the existingcollections andviews in the selected database. Each list item includes the name and other general information for the collection or view.

To access the Collections screen for a database, from theDatabases screen either:

• Click a Database Name in the main Databasesview, or
• Click a database in the left navigation.

click to enlarge

The Collections screen displays the following information for each collection in the selected database:

• Collection name
• Number of documents in the collection

Note

Compass bases the document count that appears on theCollections screen on cached metadata usingcollStats. This count might differ from the actual document count in the collection. For example, an unexpected shutdown can throw off the count. Use the db.collection.countDocuments() method for the most accurate document count.

• Average size of documents in the collection
• Total size of all documents in the collection
• Number of indexes on the collection
• Total size of all indexes on the collection
• Collation properties for the collection. Hover over a Collation banner to view the properties for that collection.

You can create new collections in an existing database.

From the Collections screen, click theCreate Collection button.

From the Collections screen, click on the trash can for the collection to delete. A confirmation dialog appears.

In the dialog, enter the name of the collection to delete.

The Collection Detail screen shows detailed information for a collection, including the documents the collection contains. To see collection details, either:

• Click a Collection Name in the mainCollections screen, or
• Click a collection in the left navigation.
• Open the collection in a new tab.

After you select a collection, Compass shows you that collection's Documents tab. Compass provides the following collection information and functionality in the detailed view:

• Manage Documents in Compass
• Import and Export Data to and from the collection
• Create an Aggregation Pipeline
• Schema Analysis
• View Query Performance
• Manage Indexes
• Set Validation Rules for Your Schema

Note

Data Lake Limitations

The following functionality is not available if you are connected to a Data Lake:

• Import data into a collection
• Schema Analysis
• View Query Performance
• Manage Indexes
• Set Validation Rules for Your Schema

You can open multiple Collection Detail screens in separate tabs. To open a new tab to view collection details:

• Creating and dropping collections is not permitted in MongoDB Compass Readonly Edition.
• The Create Collection button is not available if you are connected to a Data Lake.