Issue Summary

When filtering a Confluence Database for a tag field being empty or non-empty, it treats empty tag fields as not being empty if they have ever had a value.

Steps to Reproduce

1. Create a database that has a field with the tag type.
2. Fill in some of the fields with tags and notate which ones have ever had tags.
3. remove all tags from at least one row that has had a tag.
4. create a filter, and filter for the tag field for "is not empty"

Expected Results

Only rows with values in the field show up

Actual Results

Any rows that have ever had a value, including those that no longer have any values will show up instead.

Workaround

Currently, the only workaround is to create new rows and copy all other fields into the row to make the field for that row "empty" again, or to filter for all possible values.