From e21d06d88aabab8db0098d496ca2abb7910121a5 Mon Sep 17 00:00:00 2001
From: rmeng <rob.xu.meng@gmail.com>
Date: Sun, 26 Jan 2025 15:49:53 -0500
Subject: [PATCH] fix

---
 rust/lance/src/io/exec/knn.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/rust/lance/src/io/exec/knn.rs b/rust/lance/src/io/exec/knn.rs
index f027835cd2..e9ff1f823d 100644
--- a/rust/lance/src/io/exec/knn.rs
+++ b/rust/lance/src/io/exec/knn.rs
@@ -496,6 +496,9 @@ impl ExecutionPlan for ANNIvfSubIndexExec {
         mut children: Vec<Arc<dyn ExecutionPlan>>,
     ) -> DataFusionResult<Arc<dyn ExecutionPlan>> {
         let plan = if children.len() == 1 || children.len() == 2 {
+            if children.len() == 2 {
+                let _prefilter = children.pop().expect("length checked");
+            }
             // NOTE!!!! Prefilter transformation is ignored.
             Self {
                 input: children.pop().expect("length checked"),