Counting

Amount of documents in a collection

To return the count of documents that currently exist in a collection, you can call the LENGTH() function:

RETURN LENGTH(collection)

This type of call is optimized since 2.8 (no unnecessary intermediate result is built up in memory) and it is therefore the preferred way to determine the count. Internally, COLLECTION_COUNT() is called.

In earlier versions with COLLECT ... WITH COUNT INTO available (since 2.4), you may use the following code instead of LENGTH() for better performance:

FOR doc IN collection
    COLLECT WITH COUNT INTO length
    RETURN length