Conditional SUM for Oracle

Question

I have data as follows:

ITEM  LOCATION  UNIT RETAIL  QUANTITY 
100     KS         10          -10
200     KS         20           30

I need the sum of positive values ​​(value> 0) and the sum of negative values ​​(value <0).

How do I get the sum of a column based on a condition?

Answer 1

You can use SUM(CASE ... ):

SELECT item, location,
   SUM(CASE WHEN quantity > 0 THEN quantity ELSE 0 END) AS positive_sum,
   SUM(CASE WHEN quantity < 0 THEN quantity ELSE 0 END) AS negative_sum
FROM your_table
GROUP BY item, location;

LiveDemo

Answer 2

You can use GREATESTand LEASTin combination with the function SUM:

SQL Fiddle

Oracle 11g R2 schema setup :

CREATE TABLE table_name ( ITEM, LOCATION, QUANTITY ) AS
          SELECT 100, 'KS', -10 FROM DUAL
UNION ALL SELECT 100, 'KS', -10 FROM DUAL
UNION ALL SELECT 100, 'KS', -20 FROM DUAL
UNION ALL SELECT 100, 'KS',  10 FROM DUAL
UNION ALL SELECT 100, 'KS',   5 FROM DUAL
UNION ALL SELECT 200, 'KS',  10 FROM DUAL
UNION ALL SELECT 200, 'KS',  20 FROM DUAL
UNION ALL SELECT 200, 'KS',   5 FROM DUAL

Request 1 :

SELECT item,
       location,
       SUM( GREATEST( quantity, 0 ) ) AS positive_quantities,
       SUM( LEAST( quantity, 0 ) )    AS negative_quantities
FROM   table_name
GROUP BY item, location

Results :

| ITEM | LOCATION | POSITIVE_QUANTITIES | NEGATIVE_QUANTITIES |
|------|----------|---------------------|---------------------|
|  100 |       KS |                  15 |                 -40 |
|  200 |       KS |                  35 |                   0 |