--------------
SELECT version()
--------------

+-------------------------+
| version()               |
+-------------------------+
| 5.0.45-community-nt-log | 
+-------------------------+
1 row in set (0.00 sec)

--------------
DELETE FROM PUBACC_FR
  WHERE ( convert( frequency_assigned, DECIMAL ) >= 825 AND convert( frequency_assigned, DECIMAL ) <= 849 )
        OR
        ( convert( frequency_assigned, DECIMAL ) >= 869 AND convert( frequency_assigned, DECIMAL ) <= 894 )
--------------

Query OK, 11223 rows affected (2 min 2.67 sec)

Bye