[Docs/Design] Survey existing DB, how they use sketches, UDFs? how they expose and propagate errors?

[zzylol]

Audience

developer, designer/architect, or researcher.

Reader question or task

What's the difference between ASAPPlanner and existing DBs which support sketches?

• https://www.databricks.com/blog/apache-spark-3-apache-datasketches-new-sketch-based-approximate-distinct-counting
• https://redis.io/docs/latest/develop/data-types/probabilistic/count-min-sketch/
• something more

Required inputs and outputs

Scope and non-goals

Verification of commands, interfaces, and examples

Existing style or terminology to follow