DISTINCT values in table based value set with multiple tables in FROM clause

Summary:

I am trying to create a value set which has multiple tables in FROM clause and SELECT clause has just one column. Need DISTINCT values and for that I tried using ROWID as suggested in this forum but its not working when there are multiple tables. Below is the query I am trying to create a value set on.

SELECT DISTINCT PECT.CLASSIFICATION_NAME FROM
pay_balance_types_vl PBT , pay_balance_feeds_f PBF , pay_element_types_vl PET , PAY_ELE_CLASSIFICATIONS_VL PECT
WHERE
PBT.BALANCE_TYPE_ID = PBF.BALANCE_TYPE_ID
AND TRUNC(SYSDATE) BETWEEN PBF.EFFECTIVE_START_DATE AND PBF.EFFECTIVE_END_DATE