If field is missing on a value and fallbackObject (if specified), this value is used in its place. If not set, no value is emitted when the field is missing.
field
fallbackObject
If field is missing on a value, it is query from this object instead. If this also is missing, fallbackFieldValue is attempted.
fallbackFieldValue
If
field
is missing on a value andfallbackObject
(if specified), this value is used in its place. If not set, no value is emitted when the field is missing.