The <str> being defined must be in the same database as the
  <str> it references

  Explanation:  When creating an item, the item was named as part
  of one database, but it was being created from items of another
  database.  For example, trying to create an index in one
  database from a table in another database generates this error.

  User Action:  Create the item naming only items from the same
  database.