From 2cea5a3095db758f256827587a82393b5cca6a22 Mon Sep 17 00:00:00 2001
From: Zhen Wang <643348094@qq.com>
Date: Thu, 28 Dec 2023 21:33:31 +0800
Subject: [PATCH] [GLUTEN-4194][CORE] Clarify fallback reason when columnar
 filter is disabled (#4195)

---
 .../extension/columnar/TransformHintRule.scala              | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/gluten-core/src/main/scala/io/glutenproject/extension/columnar/TransformHintRule.scala b/gluten-core/src/main/scala/io/glutenproject/extension/columnar/TransformHintRule.scala
index 9343e54739cb..a568998f368e 100644
--- a/gluten-core/src/main/scala/io/glutenproject/extension/columnar/TransformHintRule.scala
+++ b/gluten-core/src/main/scala/io/glutenproject/extension/columnar/TransformHintRule.scala
@@ -435,8 +435,10 @@ case class AddTransformHintRule() extends Rule[SparkPlan] {
         case plan: FilterExec =>
           val childIsScan = plan.child.isInstanceOf[FileSourceScanExec] ||
             plan.child.isInstanceOf[BatchScanExec]
-          // When scanOnly is enabled, filter after scan will be offloaded.
-          if ((!scanOnly && !enableColumnarFilter) || (scanOnly && !childIsScan)) {
+          if (!enableColumnarFilter) {
+            TransformHints.tagNotTransformable(plan, "columnar Filter is not enabled in FilterExec")
+          } else if (scanOnly && !childIsScan) {
+            // When scanOnly is enabled, filter after scan will be offloaded.
             TransformHints.tagNotTransformable(
               plan,
               "ScanOnly enabled and plan child is not Scan in FilterExec")