Joint must be used for:
- Group Dims with *very *low cardinality, Example: IdCurrency (most of
bank's transactions uses < 10 currencies)
- You Have columns with same cardinality: Country_ID and Contry_txt
Check TopN feature of Kylin to precalcualte sum order by
You can allocate more memory to Ky
Hi all,
I definedsome dimensions, for example: A,B,C as joint aggregation.
When i executed query:
SELECT A,B,C, SUM(metrics) as metrics
FROM table1
WHERE DateStats <= x and DateStats >= x
GROUP BY A,B,C
LIMIT 250
Query is very fast, but Metrics (from SUM(metrics)) Value just sum data
within
