[PhysOperator] Implement dotting
We should provide dotting physical plans, i.e. MatchBase::dot()
. We have two options here:
- Implement virtual
MatchBase::name()
andMatchBase::children()
methods to get the name of a physical operator (to use it as node label) and its children (to recursively dot the plan). - Provide a visitor for physical operators and implement dotting similar to
Operator::dot()
. However, as the available physical operators depend on the used backend, we are currently unsure how to add physical operators from one backend to a unified visitor.