          return " UNION ALL ".join(
              "SELECT %s FROM DUAL" % ", ".join(row)
              for row in placeholder_rows
          )
 
</s> remove     @skipUnlessDBFeature("has_native_duration_field")
 </s> add     @skipUnlessDBFeature('supports_temporal_subtraction')
    def subtract_temporals(self, internal_type, lhs, rhs):
        if internal_type == 'DateField':
            lhs_sql, lhs_params = lhs
            rhs_sql, rhs_params = rhs
            return "NUMTODSINTERVAL(%s - %s, 'DAY')" % (lhs_sql, rhs_sql), lhs_params + rhs_params
        return super(DatabaseOperations, self).subtract_temporals(internal_type, lhs, rhs)
          return " UNION ALL ".join(
              "SELECT %s FROM DUAL" % ", ".join(row)
              for row in placeholder_rows
          )
    def subtract_temporals(self, internal_type, lhs, rhs):
        if internal_type == 'DateField':
            lhs_sql, lhs_params = lhs
            rhs_sql, rhs_params = rhs
            return "NUMTODSINTERVAL(%s - %s, 'DAY')" % (lhs_sql, rhs_sql), lhs_params + rhs_params
        return super(DatabaseOperations, self).subtract_temporals(internal_type, lhs, rhs)
keep keep keep add
 Fixed #24793 -- Unified temporal difference support. 
django/db/backends/oracle/operations.py