Query to Calculate totalcost based on description - sql

Question

I have question regarding sql script. I have a custom view, below is the data
================================================================================
ql_siteid | ql_rfqnum | ql_vendor | ql_itemnum | totalcost_option | description
================================================================================
SGCT | 1002 | VND001 | ITEM002 | 12500 |
SGCT | 1002 | VND001 | ITEM001 | 1350 |
SGCT | 1002 | VND002 | ITEM002 | 11700 |
SGCT | 1002 | VND002 | ITEM001 | 1470 | Nikon
SGCT | 1002 | VND002 | ITEM001 | 1370 | Asus
================================================================================
And i want the result like below table:
VND001 = 13850
VND002 = Asus 13070, Nikon 13170
where 13850 is come from 12500+1350, 13070 is come from 11700+1370 and 13170 is come from 11700+1470. All the cost is calculated from totalcost_option and will be group based on vendor
So please give me some advise

Answer 1

To get the exact output you required use the following statement: (where test_table is your table name):
SELECT ql_vendor || ' = ' ||
LISTAGG( LTRIM(description||' ')||totalcost, ', ')
WITHIN GROUP (ORDER BY description)
FROM (
WITH base_cost AS (
SELECT ql_vendor, SUM(totalcost_option) sumcost
FROM test_table WHERE description IS NULL
GROUP BY ql_vendor
),
individual_cost AS (
SELECT ql_vendor, totalcost_option icost, description
FROM test_table WHERE description IS NOT NULL
)
SELECT ql_vendor, sumcost + NVL(icost,0) totalcost, description
FROM base_cost LEFT OUTER JOIN individual_cost USING (ql_vendor)
)
GROUP BY ql_vendor;
Details:
The Outer select just takes the individual rows and combines them to the String-representation. Just remove it and you will get a single row for each vendor/description combination.
The inner select joins two sub-select. The first one gets the base_cost for each vendor by summing up all rows without a description. The second gets the individual cost for each row with a description.
The join combines them - and left outer joins displays the base_cost for vendors which don't have a matching row with description.

Answer 2

Assuming you have a version of Oracle 11g or later, using ListAgg will do the combination of the comma separated tuples for you. The rest of the string is generated by simply concatenating the components together from an intermediate table - I've used a derived table (X) here, but you could also use a CTE.
Edit
As pointed out in the comments, there's a whole bunch more logic missing around the Null description items I missed in my original answer.
The following rather messy query does project the required result, but I believe this may be indicative that a table design rethink is necessary. The FULL OUTER JOIN should ensure that rows are returned even if there are no base / descriptionless cost items for the vendor.
WITH NullDescriptions AS
(
SELECT "ql_vendor", SUM("totalcost_option") AS "totalcost_option"
FROM MyTable
WHERE "description" IS NULL
GROUP BY "ql_vendor"
),
NonNulls AS
(
SELECT COALESCE(nd."ql_vendor", mt."ql_vendor") AS "ql_vendor",
NVL(mt."description", '') || ' '
|| CAST(NVL(mt."totalcost_option", 0)
+ nd."totalcost_option" AS VARCHAR2(30)) AS Combined
FROM NullDescriptions nd
FULL OUTER JOIN MyTable mt
ON mt."ql_vendor" = nd."ql_vendor"
AND mt."description" IS NOT NULL
)
SELECT x."ql_vendor" || ' = ' || ListAgg(x.Combined, ', ')
WITHIN GROUP (ORDER BY x.Combined)
FROM NonNulls x
WHERE x.Combined <> ' '
GROUP BY x."ql_vendor";
Updated SqlFiddle here

Answer 3

Your logic seems to be: If description is always NULL for a vendor then you want that as the total cost. Otherwise, you want the NULL value of description added to all the other values. The following query implements this logic. The output is in a different format from your answer -- this format is more consistent with a SQL result set:
select ql_vendor,
(sum(totalcost_option) +
(case when description is not null then max(totalcost_null) else 0 end)
)
from (select v.*, max(description) over (partition by ql_vendor) as maxdescription,
sum(case when description is null then totalcost_option else 0 end) over (partition by ql_vendor) as totalcost_null
from view v
) t
where maxdescription is null or description is not null
group by ql_vendor, description;