NewPlanner creates a new Planner from the Configuration NOTE: All stateful DataSources should be initiated with the same context.Context object provided to the PlannerFactory.

PlannerFactory is the factory for the creation of the concrete DataSourcePlanner For stateful datasources, the factory should contain execution context Once the context gets cancelled, all stateful DataSources must close their connections and cleanup themselves.

ArgumentRenderConfig is used to determine how an argument should be rendered.

SourceType is used to determine the source of an argument.