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Published 20 hours ago • verified publisher icon ClickHouse

uniqMerge function in connector

Open vlauzeckas opened this issue 2 years ago • 9 comments

hi, Clickhouse have unique and very powerful functionality called Aggregate state. Basically, you can aggregate "count distinct". More about this functionality with examples could found here: https://altinity.com/blog/2017/7/10/clickhouse-aggregatefunctions-and-aggregatestate

But due to Tableau limitations its not possible to use it properly. Its possible to be used by using RAWSQL functions. Example: RAWSQLAGG_INT("uniqMerge(%1)" , [MyKPI])

Problem is that "RAWSQL pass-through functions will not work with published data sources or with Tableau extracts.": https://help.tableau.com/current/pro/desktop/en-us/functions_functions_passthrough.htm

I wonder if it would be possible to create such a function on the connector level? Like you did with "RAND()", "UNHEX([my_string])" and etc.

This aggregatestate are very powerful functionality of clickhouse, it is very pity you can't create data sources using it.

vlauzeckas avatar Feb 27 '23 20:02 vlauzeckas