ozankabak commented on code in PR #13986: URL: https://github.com/apache/datafusion/pull/13986#discussion_r1901204911
########## datafusion/physical-plan/src/execution_plan.rs: ########## @@ -110,6 +110,16 @@ pub trait ExecutionPlan: Debug + DisplayAs + Send + Sync { /// trait, which is implemented for all `ExecutionPlan`s. fn properties(&self) -> &PlanProperties; + /// Returns an error if this individual node does not conform to its invariants. + /// These invariants are typically only checked in debug mode. + /// + /// A default set of invariants is provided in the default implementation. + /// Extension nodes can provide their own invariants. + fn check_node_invariants(&self) -> Result<()> { + // TODO Review Comment: Conceptually, sanity checking is a "more general" process -- it verifies that any two operators that exchange data (i.e. one's output feeds the other's input) are compatible. So I don't think we can "change" it to be an invariant checker, but we can extend it to also check "invariants" of each individual operator (however they are defined by an `ExecutionPlan`) as it traverses the plan tree. However, we can not blindly run sanity checking after every rule. Why? Because rules have the following types regarding their input/output plan validity: - Some rules only take in valid plans and output valid plans (e.g. `ProjectionPushdown`). These are typically applied at later stages in the optimization/plan construction process. - Some take in invalid or valid plans, and always create valid plans (e.g. `EnforceSorting` and `EnforceDistribution`). These can be applied any time, but are typically applied in the middle of the optimization/plan construction process. - Some take invalid plans and yield still invalid plans (IIRC `JoinSelection` is this way). These are typically applied early in the optimization/plan construction process. As of this writing, we don't have a formal cut-off point in our list of rules whereafter plans remain valid, but I suspect they do after `EnforceSorting`. In debug/upgrade mode, we can apply `SanityCheckPlan` after every rule after that point. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For additional commands, e-mail: github-h...@datafusion.apache.org