MYSQL Union Operation with Gross, Cut & Net Amounts - mysql

Question

I need to print Gross allocation, Cut Allocation & Net Allocation issued for various offices under relevant votes. I used the following tables.
1) Total issues (Gross Allocation) are in the Table, Named "issues_tot"
+---------+------+------------+
| v_code | oid | amount |
+---------+------+------------+
| 1 | 2 | 200,000.00 |
| 1 | 3 | 80,000.00 |
| 2 | 1 | 40,000.00 |
| 3 | 2 | 150,000.00 |
+---------+------+------------+
2) Cut amounts (Cut Allocation) are in the Table, Named "cp_tot"
+--------+-----+-----------+
| v_code | oid | amount |
+--------+-----+-----------+
| 1 | 2 | 68,000.00 |
| 1 | 3 | 50,000.00 |
| 3 | 2 | 75,000.00 |
+--------+-----+-----------+
3) Table, Named "vote"
+--------+-------------------------+
| v_code | vote |
+--------+-------------------------+
| 1 | 001-2-6-3-2502 |
| 2 | 001-1-4-21-2202 |
| 3 | 101-1-2-0-1405 |
+--------+-------------------------+
4) Table, Named "office"
+-----+----------------------+
| oid | office |
+-----+----------------------+
| 1 | Weeraketiya |
| 2 | Tissamaharama |
| 3 | District Sec |
+-----+----------------------+
And desired output as follows:
+--------+------------+-----------+------------+
| v_code | Gross | Cut | Net |
+--------+------------+-----------+------------+
| 1 | 200,000.00 | 68,000.00 | 132,000.00 |
| 1 | 80,000.00 | 50,000.00 | 30,000.00 |
| 2 | 40,000.00 | 0.00 | 40,000.00 |
| 3 | 150,000.00 | 75,000.00 | 75,000.00 |
+--------+------------+-----------+------------+
02) I used the following script to generate that output
select `vote`.`vote` AS `vote`,`office`.`office` AS `office`,
`issues_tot`.`amount` AS `Gross`,
coalesce(`cp_tot`.`amount`,0) AS `Cut`,
(`issues_tot`.`amount` - coalesce(`cp_tot`.`amount`,0)) AS `Net`
from (((`vote` join `issues_tot` on((`vote`.`v_code` = `issues_tot`.`v_code`))) join
`office` on((`office`.`oid` = `issues_tot`.`oid`))) left join
`cp_tot` on((`issues_tot`.`v_code` = `cp_tot`.`v_code`)))
But it generates the following output with repeated records:
+------------+----------------+--------------+-------------+--------------+
| Vote | Office | Gross | Cut | Net |
+---------------+-------------+--------------+-------------+--------------+
| 001-2-6-3-2502| Tissamaharama | 200,000.00 | 68,000.00 |132,000.00 |
| 001-2-6-3-2502| Tissamaharama | 200,000.00 | 50,000.00 | 150,000.00 |
| 001-2-6-3-2502| District Sec | 80,000.00 | 68,000.00 | 12,000.00 |
| 001-2-6-3-2502| District Sec | 80,000.00 | 50,000.00 | 30,000.00 |
| 001-1-4-21-2202| Weeraketiya | 40,000.00 | - | 40,000.00 |
| 101-1-2-0-1405 | Tissamaharama | 150,000.00 | 75,000.00 | 75,000.00 |
+------------+-----------------+--------------+-------------+--------------+
I can not understand what was going wrong. Can anyone help me?

Answer 1

Firstly, the following query will get what you want:
select
v.vote,
o.office,
it.amount as Gross,
coalesce(ct.amount , 0) as Cut,
it.amount - coalesce(ct.amount, 0) as Net
from issues_tot it
left join cp_tot ct
on it.v_code = ct.v_code
and it.oid = ct.oid
left join vote v
on it.v_code = v.v_code
left join office o
on it.oid = o.oid
order by it.v_code
and SQLFiddle Demo Here, the only issue is that you forget to match oid between issues_tot and cp_tot.
If there is no oid criteria, the match will do like following:
# issues_tot # cp_tot
| v_code | oid | amount | | v_code | oid | amount |
+---------+------+------------+ +--------+-----+-----------+
| 1 | 2 | 200,000.00 | -> | 1 | 2 | 68,000.00 |
| 1 | 3 | 50,000.00 |
| 1 | 3 | 80,000.00 | -> | 1 | 2 | 68,000.00 |
| 1 | 3 | 50,000.00 |
| 2 | 1 | 40,000.00 | -> no record match
| 3 | 2 | 150,000.00 | -> | 3 | 2 | 75,000.00 |
so 6 records by your query is it.