hi, does pinot provide any benefits for use cases ...
# generali
II
06/23/2021, 8:29 PMhi, does pinot provide any benefits for use cases that no aggregation will be applied to query (means there is no metrics columns, all are dimension columns).
and is that the reason why metrics column does not allow other like String types
m
Mayank
06/23/2021, 8:52 PM
Do you mean you want to just fetch a bunch of rows from Pinot without any aggregation or group-by?
i
II
06/23/2021, 8:55 PM@User yes. or combination usage (like a table to server both aggregation queries but also just few rows query)
m
Mayank
06/23/2021, 8:57 PM
Yes, you can do so. Especially, if you have both aggregation and selection queries, both will work fine with Pinot
Mayank
06/23/2021, 8:58 PM
What you want to avoid is cases where you just have select * queries that are simply fetching millions of records per query, and there are no aggregation queries. In that case, you are not really utilizing the power of Pinot
i
II
06/23/2021, 9:02 PMmake sense. what about string type support for metric columns, why this is not supported? what if I just want to aggregate the count of this metrics, string type should be reasonable right?
m
Mayank
06/23/2021, 9:02 PM
You can do count(*) anytime.
Mayank
06/23/2021, 9:02 PM
Metric columns are usually ones where you would do something like
sum(metric)i
II
06/23/2021, 9:03 PMok so I need to make it as dimension columns, and avoid index by set it to
noDictionaryColumnsm
Mayank
06/23/2021, 9:03 PM
No
Mayank
06/23/2021, 9:04 PM
You just do something like
select count(<col>) from myTable where <col> != nullMayank
06/23/2021, 9:04 PM
Note, Pinot does not support nulls natively yet, so null values are replaced by a default value, which you will have to filter out
Mayank
06/23/2021, 9:05 PM
You don't need to do anything special here for just getting count
i
II
06/23/2021, 9:07 PMyeah, but I do not want to create index on this column since will not filter or aggregate on this column, how do I avoid the indexing
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