Find highest and lowest selling item in a table - oracle

Question

I have two tables as follows--
ORDERS
create table orders (
ono number(5) not null primary key,
cno number(5) references customers,
eno number(4) references employees,
received date,
shipped date);
ODETAILS
create table odetails (
ono number(5) not null references orders,
pno number(5) not null references parts,
qty integer check(qty > 0),
primary key (ono,pno));
ODETAILS Table
Now I'm trying to figure out the highest and lowest selling product. Logically PNO 10601 which has the highest QTY of 4 is the highest selling product. the following query returns the highest selling product.
SELECT PNO FROM
(SELECT od.PNO, SUM(od.QTY) AS TOTAL_QTY
FROM ODETAILS od
GROUP BY od.PNO
ORDER BY SUM(od.QTY) DESC)
WHERE ROWNUM =1
--Thanks to Bob Jarvis
How do I add a DATE WHERE clause to the SQL above so that I can find out the highest selling product for a given month(lets say DECEMBER) ? The DATE that I'm referring to is from ORDERS table and RECEIVED attribute. I guess I need to join the tables first as well

Answer 1

SQL Fiddle
Oracle 11g R2 Schema Setup:
create table orders (
ono number(5) not null primary key,
cno number(5),
eno number(4),
received date,
shipped date
);
INSERT INTO orders
SELECT 1020, 1, 1, DATE '2015-12-21', NULL FROM DUAL UNION ALL
SELECT 1021, 1, 1, DATE '2015-12-20', DATE '2015-12-20' FROM DUAL UNION ALL
SELECT 1022, 1, 1, DATE '2015-12-18', DATE '2015-12-20' FROM DUAL UNION ALL
SELECT 1023, 1, 1, DATE '2015-12-21', NULL FROM DUAL UNION ALL
SELECT 1024, 1, 1, DATE '2015-12-20', DATE '2015-12-20' FROM DUAL;
create table odetails (
ono number(5) not null references orders(ono),
pno number(5) not null,
qty integer check(qty > 0),
primary key (ono,pno)
);
INSERT INTO odetails
SELECT 1020, 10506, 1 FROM DUAL UNION ALL
SELECT 1020, 10507, 1 FROM DUAL UNION ALL
SELECT 1020, 10508, 2 FROM DUAL UNION ALL
SELECT 1020, 10509, 3 FROM DUAL UNION ALL
SELECT 1021, 10601, 4 FROM DUAL UNION ALL
SELECT 1022, 10601, 1 FROM DUAL UNION ALL
SELECT 1022, 10701, 1 FROM DUAL UNION ALL
SELECT 1023, 10800, 1 FROM DUAL UNION ALL
SELECT 1024, 10900, 1 FROM DUAL;
Query 1 - The onoand pnos for the pno which has sold the maximum total quantity in December 2015:
SELECT ono,
pno,
TOTAL_QTY
FROM (
SELECT q.*,
RANK() OVER ( ORDER BY TOTAL_QTY DESC ) AS rnk
FROM (
SELECT od.ono,
od.PNO,
SUM( od.QTY ) OVER ( PARTITION BY od.PNO ) AS TOTAL_QTY
FROM ODETAILS od
INNER JOIN
orders o
ON ( o.ono = od.ono )
WHERE TRUNC( o.received, 'MM' ) = DATE '2015-12-01'
-- WHERE EXTRACT( MONTH FROM o.received ) = 12
) q
)
WHERE rnk = 1
Change the WHERE clause to get the results for any December rather than just December 2015.
Results:
| ONO | PNO | TOTAL_QTY |
|------|-------|-----------|
| 1021 | 10601 | 5 |
| 1022 | 10601 | 5 |
Query 2 - The ono and pnos for the items which have sold the maximum quantity in a single order in December 2015:
SELECT ono,
pno,
qty
FROM (
SELECT od.*,
RANK() OVER ( ORDER BY od.qty DESC ) AS qty_rank
FROM ODETAILS od
INNER JOIN
orders o
ON ( o.ono = od.ono )
WHERE TRUNC( o.received, 'MM' ) = DATE '2015-12-01'
-- WHERE EXTRACT( MONTH FROM o.received ) = 12
)
WHERE qty_rank = 1
Change the WHERE clause to get the results for any December rather than just December 2015.
Results:
| ONO | PNO | QTY |
|------|-------|-----|
| 1021 | 10601 | 4 |

Answer 2

... where received between to_date('12/01/2015','MM/DD/YYYY') and to_date('12/31/2015','MM/DD/YYYY')

Answer 3

I believe I have solved it!
SELECT PNO
FROM (SELECT OD.PNO, SUM(OD.QTY) AS TOTAL_QTY
FROM ODETAILS OD INNER JOIN ORDERS ON OD.ONO = ORDERS.ONO
WHERE EXTRACT(MONTH FROM ORDERS.RECEIVED) = &MONTH_NUMBER
GROUP BY OD.PNO
ORDER BY SUM(OD.QTY) DESC)
WHERE ROWNUM =1;

Answer 4

You can add some to_char calls to your query on the date columns to parse out year and month, or just month if you want all years divided by month (month and year seems more useful), then add that to your where clause. See my self-contained example:
with odetails as
(
select 1 as ono, 1 as pno, 4 as qty from dual
union all
select 1 as ono, 2 as pno, 1 as qty from dual
union all
select 1 as ono, 3 as pno, 2 as qty from dual
union all
select 1 as ono, 4 as pno, 1 as qty from dual
union all
select 2 as ono, 2 as pno, 1 as qty from dual
union all
select 2 as ono, 3 as pno, 2 as qty from dual
),
orders as
(
select 1 as ono, 1 as cno, 1 as eno, to_date('2015-10-12', 'YYYY-MM-DD') as received, to_date('2015-10-15', 'YYYY-MM-DD') as shipped from dual
union all
select 2 as ono, 1 as cno, 1 as eno, to_date('2015-11-12', 'YYYY-MM-DD') as received, to_date('2015-11-15', 'YYYY-MM-DD') as shipped from dual
)
select pno
from
(
select od.pno, Sum(od.qty) as total_qty, to_char(received, 'YYYY-MM') as year_month
from odetails od
join orders o
on o.ono = od.ono
group by od.pno, to_char(received, 'YYYY-MM')
order by Sum(od.qty) desc
)
where rownum = 1
and year_month = '2015-11'
;
This gives you PNO of 3, since it has the highest quantity in november of 2015.