Index <Indexname> is used to enforce the full-text key on table <Tablename> and must not be null. (Visual Database Tools)
You are performing an operation that will allow null values within the column that is used as a key for full-text indexing of this table. Proceed with the operation to disable full-text indexing for this table or cancel the operation to keep full-text indexing.
See Also
Concepts
Error Messages in Visual Database Tools