Setting active null
In HL7, a message field can contain an active null value, which is represented by quotations in the field (""). The interpretation of this value is that the receiver should clear the existing value in that field. This is in contrast with an empty field, so that the field in the receiver’s side should remains as-is. To set the message field as active null, that is, the string "", during translation:
- In the Source panel for the COPY action, right-click and select @active_null from the menu, and then select the Destination field.
- After translation, the Destination field is shown as "" for @active_null.
- Clear the @active_null value by copying "@null" or "=" to the Destination field. This causes the field to become empty.