Exclude a certian field or make it Null inside a AQL query

Question

I have problem. I have a collection orders. I want to get all documents and all field except the field dataOriginSystem inside metaData. Is there an option to exclude this value, or make it null?

SELECT * EXCEPT(ColumnNameX, [ColumnNameY, ...])
FROM TableA

This my collection orders:

[
{'_id': 'orders/213123',
 'contactEditor': {'name': 'Max Power',
  'phone': '1234567',
  'email': '[email protected]'},
 'contactSoldToParty': {'name': 'Max Not',
  'phone': '123456789',
  'email': '[email protected]'},
 'isCompleteDelivery': False,
 'metaData': {'dataOriginSystem': 'Goods',
  'dataOriginWasCreatedTime': '10:12:12',},
 'orderDate': '2021-02-22',
 'orderDateBuyer': '2021-02-22',
},
{'_id': 'orders/12323',
 'contactEditor': {'name': 'Max Power2',
  'phone': '1234567',
  'email': '[email protected]'},
 'contactSoldToParty': {'name': 'Max Not',
  'phone': '123456789',
  'email': '[email protected]'},
 'isCompleteDelivery': False,
 'metaData': {'dataOriginSystem': 'Goods',
  'dataOriginWasCreatedTime': '10:12:12',},
 'orderDate': '2021-02-22',
 'orderDateBuyer': '2021-02-22',
 },
]

AQL

FOR doc IN orders RETURN doc

I want something like

FOR doc IN orders RETURN doc WITHOUT metaData_dataOriginSystem
FOR doc IN orders RETURN doc AND metaData_dataOriginSystem = NULL

So that the returned documents do not have the field metaData_dataOriginSystem or the field should be Null

What I want (the other fields should all exist!)

[
{'_id': 'orders/213123',
 ...
 'isCompleteDelivery': False,
 'metaData': {<Removed>,
  'dataOriginWasCreatedTime': '10:12:12',},
 ...
},
OR
{'_id': 'orders/12323',
 ...
 'isCompleteDelivery': False,
 'metaData': {'dataOriginSystem': Null,
  'dataOriginWasCreatedTime': '10:12:12',},
 ...
 },
]

Answer 1

Use UNSET() or UNSET_RECURSIVE().

UNSET(document, attributeName1, attributeName2, ... attributeNameN) → doc

Remove the attributes attributeName1 to attributeNameN from document. All other attributes will be preserved.

FOR doc IN orders RETURN UNSET( doc, "orderData", "dataOriginSystem")

---

If you want to remove a nested value, you need to Merge

FOR doc IN orders RETURN MERGE(doc, {metaData: UNSET(doc.metaData, "dataOriginSystem")})