SQL & PL/SQL :: Query To Generate Report For Shopping Store

I've below test case

CREATE TABLE MYMERCHANT
(
SRNONUMBER(5),
PARENTSRNONUMBER(5),
LEVELNONUMBER(5),
LEVELNAMEVARCHAR2(25)
) ;
INSERT INTO MYMERCHANT(SRNO, PARENTSRNO, LEVELNO, LEVELNAME ) VALUES ( 1, NULL, 101, 'HQ1' ) ;
INSERT INTO MYMERCHANT(SRNO, PARENTSRNO, LEVELNO, LEVELNAME ) VALUES ( 2, 1, 102, 'DIV1' ) ;
INSERT INTO MYMERCHANT(SRNO, PARENTSRNO, LEVELNO, LEVELNAME ) VALUES ( 3, 1, 103, 'DIV2' ) ;
[code]........

Structure is like above. There is a Head Quarter (HQ1) under which we have different division like (DIV1 and DIV2). Under division we have different location where our shopping stores are operating and transactions are done (LOC1, LOC2 for DIV1) and (LOC3 for DIV2) respectively.

DESIRED OUTPUT
User can generate reports at two levels i.e. Head Quarter level and Division Level.

When user wants report at Head Quarter Level :
Page 1 (Should Display as below)
HQ1 DIV1 LOC1 450
HQ1 DIV1 LOC2 400
HQ1 DIV2 LOC3 600

Page 2 (Should Display as below)
HQ1 DIV1 LOC1 450
HQ1 DIV1 LOC2 400

Page 3 (Should Display as below)
HQ1 DIV2 LOC3 600

When user wants report at Division Level : eg DIV1
Page 1 (Should Display as below)
HQ1 DIV1 LOC1 450
HQ1 DIV1 LOC2 400