Problem While Writing Query

Question

Hi:
There are three tables,
*1.TbReg*
reg_no,reg_name
Data:
RO1 Reg1
RO2 Reg2
RO3 Reg3
*2.TbZbr*
br_no,reg_no
Data:
092 RO1
013 RO1
020 RO3
*3.TbLM_Mast*
LM_no,br_no
Data:
1 013
2 013
3 020
Required O/p:
Reg_name | NoOfLeads |
RO1 | 2 |
RO2 | 0 |
RO3 | 1 |
From Above tables i want to write query for,
select total number of leads available in TbLM_Mast against each branch(*br_no*) from TbZbr,
and compare same reg_no with TbReg table and display required O/p/
So, how to write this query...?
Can any body help me...
Thank You,
Anup Desai

Answer 1

How about this:
with TbReg(reg_no,reg_name) as
(select 'RO1','Reg1' from dual union all
select 'RO2','Reg2' from dual union all
select 'RO3','Reg3' from dual
TbZbr(br_no,reg_no)
as
(select '092','RO1' from dual union all
select '013','RO1' from dual union all
select '020','RO3' from dual
TbLM_Mast(LM_no,br_no)
as
(select 1, '013' from dual union all
select 2, '013' from dual union all
select 3, '020' from dual)
SELECT TbReg.Reg_No,COUNT(TbLM_Mast.br_no)
FROM   TbReg
LEFT OUTER JOIN TbzBr
ON TbzBr.reg_no = TbReg.reg_no
LEFT OUTER JOIN TbLM_Mast
ON TbLM_Mast.br_no = TbzBr.br_no
GROUP BY TbReg.Reg_No