Applying LIMIT (dimen.) TO TOP (...) BASEDON (...) structure in OLAP_TABLE

Question

Hi
I'd like to know how to apply structure
LIMIT dimension TO TOP (number of top member performers) BASEDON (measure)
in OLAP_TABLE.
For instance I have a cube SALES with 2 measures: SALES_VALUE and QUANTITY and a dimension PRODUCT with two levels: TOTAL and PRODUCT_NAME. Then I want to list 3 products with the highest SALES_VALUE and QUANTITY > 100.
I can create for example such query:
SELECT sales_val, quant, product_dsc
FROM TABLE(OLAP_TABLE(
'test_schema.test_aw DURATION SESSION',
null,
null,
MEASURE sales_val FROM sales_value
MEASURE quant FROM quantity
DIMENSION product WITH
HIERARCHY product_parentrel
INHIERARCHY product_inhier
ATTRIBUTE product_dsc FROM product_description
ROW2CELL r2c'))
WHERE
OLAP_CONDITION(R2C, 'LIMIT product TO product_levelrel eq ''PRODUCT_NAME''', 1)=1
AND OLAP_EXPRESSION_BOOL(R2C, ' quantity gt 100')=1
AND OLAP_CONDITION(R2C, 'LIMIT product TO TOP 3 BASEDON sales_value, 1)=1;  ???????
Instruction above does not work completely well, because it will give 3 rows with top values of SALES_VALUE measure, but in this case OLAP_CONDITION(R2C, 'LIMIT product TO product_levelrel eq ''PRODUCT_NAME''', 1)=1 is not fulfilled (row with values of TOTAL_PRODUCT level appears).
One can create such query:
SELECT sales_val, quant, product_dsc
FROM TABLE(OLAP_TABLE(
'test_schema.test_aw DURATION SESSION',
null,
*'LIMIT product TO TOP 3 BASEDON sales_value', ?????*
MEASURE sales_val FROM sales_value
MEASURE quant FROM quantity
DIMENSION product WITH
HIERARCHY product_parentrel
INHIERARCHY product_inhier
ATTRIBUTE product_dsc FROM product_description
ROW2CELL r2c'))
where
OLAP_CONDITION(R2C, 'LIMIT product TO product_levelrel eq ''PRODUCT_NAME''', 1)=1
AND OLAP_EXPRESSION_BOOL(R2C, ' quantity gt 100')=1;
It leads to the same result as the first query.
What shuold I do to make OLAP_CONDITION(R2C, 'LIMIT product TO product_levelrel eq ''PRODUCT_NAME''', 1)
fulfill in query above?
I can add that query below works as it should (LIMIT TO TOP... omitted).
SELECT sales_val, quant, product_dsc
FROM TABLE(OLAP_TABLE(
'test_schema.test_aw DURATION SESSION',
null,
null,
MEASURE sales_val FROM sales_value
MEASURE quant FROM quantity
DIMENSION product WITH
HIERARCHY product_parentrel
INHIERARCHY product_inhier
ATTRIBUTE product_dsc FROM product_description
ROW2CELL r2c'))
WHERE
OLAP_CONDITION(R2C, 'LIMIT product TO product_levelrel eq ''PRODUCT_NAME''', 1)=1
AND OLAP_EXPRESSION_BOOL(R2C, ' quantity gt 100')=1;
Thank you in advance for any help
Peter

Answer 1

Peter, Yes, I hadn't considered the condition sales_value greater than 100 in my mail.
You can try either of the below limit cmds to include that condition too:
limit product to limit(limit(limit(product to (product_levelrel eq 'PRODUCT_NAME') AND (sales_value gt 100)) keep top 3 basedon sales_value) sort top 3 basedon sales_value)
-or-
limit product to limit(limit(limit(limit(product to product_levelrel eq 'PRODUCT_NAME') keep sales_value gt 100) keep top 3 basedon sales_value) sort top 3 basedon sales_value)
I dont think one can be sure that having separate olap_condition filters for each condition will work fine all the time. To simulate the cascading of AND operations of where clause (filters) in SQL, we can use the nested limit() function to act on progressively smaller/better qualified resultsets (cells). SQL query would apply the AND filters in any manner or order that the optimizer deems fit whereas using the limit function with keyword "keep" within it indicates an implicit order of filters. SQL query with multiple olap_conditions might rank and find top 3 -or- bottom 5 before it applies the filter "sales_value gt 100". In such a case, you may find that the query will return no rows or return only the top 1 or 2 out of top 3 which are gt 100 -or- in case of bottom, return no rows or return less than 5 members (only those above 100) -- not necessarily 3 "top 3" or 5 "bottom 5" members.
rgds
Shankar