zhile

Another point I think is if we have this we can read stripes in parallel which make it more quickly.

How about user defined aggregation function? Or user defined table function like Snowflake: https://docs.snowflake.com/en/developer-guide/udf/java/udf-java-tabular-functions.html Which can help users to process blocks of data and output only one row result.

Also this big task https://github.com/ClickHouse/ClickHouse/issues/23194

@alexey-milovidov Thanks for your explanation and I'm looking forward to those new changes of ClickHouse and hoping it to be better!