Join SQL query not giving desired result - sql

Question

I have separate queries with me as follows:
SELECT c.id
FROM claim c,
company co,
customer cu
WHERE c.company_id = co.id
AND c.customer_id = cu.id
AND co.company_code = 'LTO'
AND cu.customer_no = '021540'
AND c.invoice_number IS NOT NULL
AND c.invoice_date IS NULL
AND c.invoice_number = '20170331'
SELECT Sum(price)
FROM replaced_part
WHERE claim_id IN ( 628099, 674047, 1182523, 1282549,
1479834, 1480585, 1487452, 1515238 );
SELECT Sum(price)
FROM allowance
WHERE claim_id IN ( 628099, 674047, 1182523, 1282549,
1479834, 1480585, 1487452, 1515238 );
I was trying to group together all the above queries into one using sql equi join as follows:
select co.company_Code,
cu.customer_No,
c.invoice_Number,
sum(r.price),
sum(a.price)
FROM claim c INNER JOIN company co ON c.COMPANY_ID=co.ID
INNER JOIN customer cu ON c.CUSTOMER_ID=cu.ID
INNER JOIN replaced_part r ON r.claim_id=c.id
INNER JOIN allowance a ON a.claim_id = c.id
WHERE co.company_code = 'LTO' and cu.customer_no='021540' and
c.INVOICE_NUMBER is not null and c.INVOICE_DATE is null and
c.INVOICE_NUMBER='20170331'
GROUP BY co.company_Code, cu.customer_No, c.invoice_Number
But I am not getting the desired result(Query execute successfully but the sum is incorrect) as I am getting after running the 3 separate queries defined above... What is the problem here in my query created using equi join??
Relationship between tables are claim ->(one to one) -> company ->(one to one) -> customer ->(one to many) ->Replaced_Part ->(one to many) -> allowance

Answer 1

Please try to use left join for Replaced_Part and allowance
select co.company_Code
, cu.customer_No
, c.invoice_Number
, (SELECT sum(r.price) FROM replaced_part r WHERE r.claim_id = c.id)
, (SELECT sum(a.price) FROM allowance a WHERE a.claim_id = c.id)
FROM claim c
INNER JOIN company co
ON c.COMPANY_ID=co.ID
INNER JOIN customer cu
ON c.CUSTOMER_ID=cu.ID
WHERE co.company_code = 'LTO'
AND cu.customer_no='021540'
AND c.INVOICE_DATE is null
AND c.INVOICE_NUMBER='20170331'
GROUP BY co.company_Code
, cu.customer_No
, c.invoice_Number

Answer 2

try to use temporary table, combine all the tables and make a temporary table, then fire your conditions on that table.
Example :
select co.company_Code,
cu.customer_No,
c.invoice_Number,
sum(r.price),
sum(a.price)
into #temp from (claim c
INNER JOIN company co ON c.COMPANY_ID=co.ID
INNER JOIN customer cu ON c.CUSTOMER_ID=cu.ID
INNER JOIN replaced_part r ON r.claim_id=c.id
INNER JOIN allowance a ON a.claim_id = c.id
and then use your conditions on #temp. like
select * from #temp
WHERE company_code = 'LTO' and customer_no='021540' and
INVOICE_NUMBER is not null and INVOICE_DATE is null and
INVOICE_NUMBER='20170331'
GROUP BY company_Code, customer_No, invoice_Number
Hope this will work for you.