> For the complete documentation index, see [llms.txt](https://docs.libum.io/nexum/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.libum.io/nexum/resources/nil-field-support.md).

# Nil Field Support

To send a nil value to SymXchange, use the exact JSON marker `{"nxNil": true}` as the field value. NexumAPI sends this marker as `xsi:nil="true"` in the SOAP request. This is different from leaving the field out of the request.

JSON `null` is not a nil marker. It keeps its normal behavior as an omitted optional field.

## Example: Set a Loan Close Date to Nil

This [updateLoanByID](/nexum/symxchange/api-reference/v2022.01/accountservice/loan/updateloan.md) request sends a nil value for a loan's `CloseDate` field.

```json
{
  "Credentials": {
    "AdministrativeCredentials": {
      "Password": "suwn37834b91&"
    }
  },
  "AccountNumber": "0000017369",
  "LoanId": "L001",
  "LoanUpdatableFields": {
    "CloseDate": { "nxNil": true }
  }
}
```

Use `{"nxNil": true}` only for optional fields that the operation accepts as nil. The marker must contain exactly the `nxNil` property set to `true`. Required fields, credentials, and fields that do not support nil values must still be supplied with a value of the documented type.

For update operations, the effect of a nil field is determined by the underlying SymXchange operation and field. Omitting a field continues to use the operation's normal behavior for an unspecified field.


---

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