feat: support pushdown alias on dynamic filter with ProjectionExec

datafusion/physical-expr/src/utils/mod.rs

@@ -23,6 +23,7 @@ use std::sync::Arc;
 
 use crate::PhysicalExpr;
 use crate::PhysicalSortExpr;
+use crate::expressions::UnKnownColumn;
 use crate::expressions::{BinaryExpr, Column};
 use crate::tree_node::ExprContext;
 
@@ -238,6 +239,21 @@ pub fn collect_columns(expr: &Arc<dyn PhysicalExpr>) -> HashSet<Column> {
     columns
 }
 
+pub fn have_unknown_columns(expr: &Arc<dyn PhysicalExpr>) -> bool {
+    let mut found = false;
+    expr.apply(|e| {
+        if e.as_any().downcast_ref::<UnKnownColumn>().is_some() {
+            found = true;
+            Ok(TreeNodeRecursion::Stop)
+        } else {
+            Ok(TreeNodeRecursion::Continue)
+        }
+    })
+    .expect("no way to return error during recursion");
+
+    found
+}
+
 /// Re-assign indices of [`Column`]s within the given [`PhysicalExpr`] according to
 /// the provided [`Schema`].
 ///

datafusion/physical-plan/src/filter_pushdown.rs

@@ -38,7 +38,9 @@ use std::collections::HashSet;
 use std::sync::Arc;
 
 use datafusion_common::Result;
-use datafusion_physical_expr::utils::{collect_columns, reassign_expr_columns};
+use datafusion_physical_expr::utils::{
+    collect_columns, have_unknown_columns, reassign_expr_columns,
+};
 use datafusion_physical_expr_common::physical_expr::PhysicalExpr;
 use itertools::Itertools;
 
@@ -339,7 +341,9 @@ impl ChildFilterDescription {
                 .iter()
                 .all(|col| child_column_names.contains(col.name()));
 
-            if all_columns_exist {
+            let have_unknown_columns = have_unknown_columns(filter);
+
+            if all_columns_exist && !have_unknown_columns {
                 // All columns exist in child - we can push down
                 // Need to reassign column indices to match child schema
                 let reassigned_filter =

datafusion/physical-plan/src/lib.rs

@@ -92,6 +92,7 @@ pub mod streaming;
 pub mod tree_node;
 pub mod union;
 pub mod unnest;
+pub mod util;
 pub mod windows;
 pub mod work_table;
 pub mod udaf {