resolve comments

src/frontend/planner_test/tests/testdata/predicate_pushdown.yaml

@@ -129,7 +129,7 @@
     └─LogicalAgg { group_key: [t.v1, t.v2, t.v3], aggs: [count, count(1:Int32)] }
       └─LogicalProject { exprs: [t.v1, t.v2, t.v3, 1:Int32] }
         └─LogicalScan { table: t, columns: [t.v1, t.v2, t.v3], predicate: (t.v1 = 10:Int32) AND (t.v2 = 20:Int32) AND (t.v3 = 30:Int32) AND (t.v2 > t.v3) }
-- name: filter project set transpose
+- name: filter project set transpose TODO(https://github.com/risingwavelabs/risingwave/issues/8591)
   sql: |
     create table t(v1 int, v2 int, v3 int, arr int[]);
     with cte as (select v1, v2, v3, unnest(arr) as arr_unnested from t) select * from cte where v1=10 AND v2=20 AND v3=30 AND arr_unnested=30;

src/frontend/src/optimizer/plan_node/logical_project_set.rs

@@ -239,6 +239,7 @@ impl fmt::Display for LogicalProjectSet {
 
 impl ColPrunable for LogicalProjectSet {
     fn prune_col(&self, required_cols: &[usize], ctx: &mut ColumnPruningContext) -> PlanRef {
+        // TODO: column pruning for ProjectSet https://github.com/risingwavelabs/risingwave/issues/8593
         let mapping = ColIndexMapping::with_remaining_columns(required_cols, self.schema().len());
         let new_input = {
             let input = self.input();
@@ -271,6 +272,7 @@ impl PredicatePushdown for LogicalProjectSet {
         predicate: Condition,
         ctx: &mut PredicatePushdownContext,
     ) -> PlanRef {
+        // TODO: predicate pushdown https://github.com/risingwavelabs/risingwave/issues/8591
         gen_filter_and_pushdown(self, predicate, Condition::true_cond(), ctx)
     }
 }