databaseoracle-databasedata-warehouserolap

How to write query without "Cube" function in oracle?

I am working at ROLAP on Oracle and i have this Fact Table : Sales(market_id,item_id,sale), and i have this query :

SELECT market_id,item_id,SUM(sale) FROM Sales
GROUP BY CUBE(market_id,item_id);

Is there another way to get the same results but without using "CUBE" function ?

Solution

  • Te below query is an equivalent to a query with CUBE(market_id,item_id) clause (gives the same resultset).
    But it will be slower, it will read the table 4 times - CUBE is optimized, it reads the table only once.

    SELECT market_id,item_id,SUM(sale) 
FROM Sales
GROUP BY market_id,item_id
UNION ALL
SELECT market_id,NULL,SUM(sale) 
FROM Sales
GROUP BY market_id,NULL
UNION ALL
SELECT NULL,item_id,SUM(sale) FROM Sales
GROUP BY NULL,item_id
UNION ALL
SELECT NULL, NULL,SUM(sale) 
FROM Sales
GROUP BY NULL, NULL