Use case

Improve clickhouse usability with BI tools which doesn't know anything about AggregationFunction data type

A clear and concise description of what is the intended usage scenario is.

Describe the solution you'd like

auto_finalize_aggregation_states setting which will do the following:

1. For system.tables, DESC table_name return not AggregationFunction(xxxx), but resulting type.
2. For columns with AggregationFunction datatype:
   2.1. For non-aggregation queries will transparently apply finalizeAggregation() function.
   2.2. For aggregation queries will transparently apply -Merge combinator for aggregation functions around them.