From the top of my head, RFC details are stored in ITSM_Changes table. This will have a link to the REP_CODES table, for all the code type fields (Status, category, closure code, etc). And the REP_CODES table will be related to the REP_CODES_TEXT table. REP_CODES_TEXT table will hold the Status text, in your case. So to get the changes and their status, select the changes from ITSM_Changes and then the status from REP_CODES_TEST. Remember to relate these tables in your sql statement.
I have the same script for Incidents. I think that you can transform it for Changes without problems.
SELECT T1.INC_ID AS [ID] ,T3.RCT_NAME AS [Status] FROM ITSM_INCIDENTS T1 ,REP_CODES T2 ,REP_CODES_TEXT T3 WHERE (T3.RCT_LNG_OID = 1049) --this condition --is necessary if you use localization. --1049 - Russian code page and T2.RCD_OID = T1.INC_STA_OID and T3.RCT_RCD_OID = T2.RCD_OID
another point is that I want to link the Change Status with its Closure Code. Is the Closure Code at the REP_CODES table or at the ITSM_CODES table ?? IÂ´m asking this because I donÂ´t have the complete Data Dictionary of HP SD.