size

Selects documents where the value of a field is an array of size size (exactly).

This operator cannot accept a range of values. To select documents based on fields with different numbers of elements, create a counter field that you increment when you add elements to a field.

Queries cannot use indexes for this portion of the query, but other parts of the query may use indexes if applicable.

Example

class User(
    val grades: List<Int>,
)

collection.find {
    User::grades size 3
}

External resources

• Official documentation