Xiening, The bug is "obvious" when you open a Graphviz diagram. Just wondering: have you tried?
The issue is EnumerableTableFunctionScan consumes Subset#0.NONE.[0] as an input, which is never implementable. The fix is trivial: EnumerableTableFunctionScanRule must convert inputs to EnumerableConvention (e.g. see how EnumerableProjectRule converts input to enumerable) So getInputs() should be replaced with convertList(rel.getInputs(), EnumerableConvention.INSTANCE) Can you please try that? Vladimir
