combine multiple queries into single query - oracle11g

Question

I have 2 queries and calling a function 2 times I need call the function one time only based on msg_sys_no count and msg_trans_type.
please find the queries mentioned below and provide me the solution for merging into single.
SELECT COUNT(DISTINCT b1.msg_sys_no) INTO A
FROM tra_message b1
WHERE TO_CHAR(b1.msg_when_created,'YYYY-MM-DD') = in_start_date
AND b1.msg_service_provider = in_svc_provider
AND b1.msg_trans_type = 'TRADE1'
AND get_transaction_status_func(b1.msg_sys_no, b1.msg_trans_type) = 'S';
SELECT COUNT(DISTINCT b1.msg_sys_no) INTO B
FROM tra_message b1
WHERE TO_CHAR(b1.msg_when_created,'YYYY-MM-DD') = in_start_date
AND b1.msg_service_provider = in_svc_provider
AND b1.msg_trans_type = 'TRADE2'
AND get_transaction_status_func(b1.msg_sys_no, b1.msg_trans_type) = 'S';

Answer 1

What about something like this:
WITH tra_data
AS (SELECT *
FROM tra_message
WHERE TO_CHAR (msg_when_created, 'YYYY-MM-DD') = in_start_date
AND msg_service_provider = in_svc_provider
AND get_transaction_status_func (msg_sys_no, msg_trans_type) =
'S')
SELECT COUNT (*)
FROM tra_data
WHERE msg_trans_type = 'TRADE1'
UNION
SELECT COUNT (*)
FROM tra_data
WHERE msg_trans_type = 'TRADE2'

Answer 2

The problem is your AND b1.msg_trans_type IN ('TRADE1','TRADE2') condition.
Try something like this:
select COUNT(DISTINCT a) TRADE1,
COUNT(DISTINCT b) TRADE2
into A,B
from (
select case when b1.msg_trans_type = 'TRADE1'
then b1.msg_sys_no
else null end as a,
case when b1.msg_trans_type = 'TRADE2'
then b1.msg_sys_no
else null end as b
FROM tra_message b1
WHERE TO_CHAR(b1.msg_when_created,'YYYY-MM-DD') = in_start_date
AND b1.msg_service_provider = in_svc_provider
AND b1.msg_trans_type IN ('TRADE1','TRADE2')
AND get_transaction_status_func(b1.msg_sys_no, b1.msg_trans_type) = 'S'
);