How to aggregate on the same column? - database

Question

I am trying to figure out which seems very simple but I am not able to figure out a way to do same.
Consider following table and data,
create table dummy_query
(id varchar2(20), amount number(10,2), memo varchar(20));
insert into dummy_query values('1', 10.00, 'Memo');
insert into dummy_query values('1', 20.00, 'Memo1');
I want to get the values as:
Id MemoValue Memo1Value TotalSum
----------
1 10.00 20.00 30.00
Is there any way to get data in this manner?
Thanks!

Answer 1

SQL Fiddle
Oracle 11g R2 Schema Setup:
create table dummy_query (id, amount, memo) AS
SELECT '1', 10.00, 'Memo' FROM DUAL
UNION ALL SELECT '1', 20.00, 'Memo1' FROM DUAL
UNION ALL SELECT '1', 30.00, 'Memo2' FROM DUAL;
Query 1:
If the TotalSum is the total of all memo amounts (and not just Memo and Memo1) then you can do:
SELECT ID,
SUM( CASE memo WHEN 'Memo' THEN amount END ) AS MemoValue,
SUM( CASE memo WHEN 'Memo1' THEN amount END ) AS Memo1Value,
SUM( amount ) AS TotalSum
FROM dummy_query
GROUP BY id
Results:
| ID | MEMOVALUE | MEMO1VALUE | TOTALSUM |
|----|-----------|------------|----------|
| 1 | 10 | 20 | 60 |
Query 2:
But if the TotalSum is just MemoValue + Memo1Value then add in a where clause:
SELECT ID,
SUM( CASE memo WHEN 'Memo' THEN amount END ) AS MemoValue,
SUM( CASE memo WHEN 'Memo1' THEN amount END ) AS Memo1Value,
SUM( amount ) AS TotalSum
FROM dummy_query
WHERE memo IN ( 'Memo', 'Memo1' )
GROUP BY id
Results:
| ID | MEMOVALUE | MEMO1VALUE | TOTALSUM |
|----|-----------|------------|----------|
| 1 | 10 | 20 | 30 |
Query 3:
Or, if you need to include all rows for another reason, then you could do:
SELECT ID,
SUM( CASE memo WHEN 'Memo' THEN amount END ) AS MemoValue,
SUM( CASE memo WHEN 'Memo1' THEN amount END ) AS Memo1Value,
SUM( CASE WHEN memo IN ( 'Memo', 'Memo1' ) THEN amount END ) AS TotalSum
FROM dummy_query
GROUP BY id
Results:
| ID | MEMOVALUE | MEMO1VALUE | TOTALSUM |
|----|-----------|------------|----------|
| 1 | 10 | 20 | 30 |

Answer 2

Im not very familiar with PIVOT but what you have tried I did build query on that. Hope this is out put you need -
SELECT a.*, b.SUM_AMT
FROM ((SELECT ID, amount, memo FROM dummy_query) PIVOT (SUM (amount)
FOR (memo)
IN ('Memo', 'Memo1'))) a,
( SELECT ID, SUM (AMOUNT) "SUM_AMT"
FROM dummy_query
GROUP BY id) b
WHERE a.id = b.id
There can be better ways to reslove this so lets see what other folks have to share.

Answer 3

Solution with pivot, which you already started:
select id, memo, memo1, memo+memo1 msum from (
select * from dummy_query
pivot (sum(amount) for (memo) in ('Memo' memo,'Memo1' memo1)))
and more traditional, without pivot:
select id, memo, memo1, memo1+memo msum from (
select id,
sum(case when memo='Memo' then amount end) memo,
sum(case when memo='Memo1' then amount end) memo1
from dummy_query group by id)
SQLFiddle