I doubt that. What you did doesn’t really translate well to tags (as you’ve found out, I guess). Since the “tag” probably came from the document itself, you could try DT’s amount related functions/scripts. Alternatively, you’d have to write your own script:
- get all records in the current database with a tag like
amount=– that will probably be very slow - remove “amount=” from the tag
- copy the rest to your custom metadata field
Though I don’t understand why you’d want a text field to contain a number – why not a number field?