How to find QC10 bug history by using SQL?

SELECT AL.AU_USER, AL.AU_TIME, AP.AP_PROPERTY_NAME,

       AP.AP_NEW_VALUE, AP.AP_NEW_LONG_VALUE, AP.AP_NEW_DATE_VALUE,AL.AU_ACTION

FROM AUDIT_LOG AL, AUDIT_PROPERTIES AP, BUG B

WHERE (AL.AU_ACTION_ID = AP.AP_ACTION_ID)

  AND (TO_CHAR(B.BG_BUG_ID) = TO_CHAR(AL.AU_ENTITY_ID))

  AND (B.BG_BUG_ID = '20480')

  AND (AL.AU_ENTITY_TYPE = 'BUG')

ORDER BY AU_TIME ASC