diff --git a/src/main/java/org/tikv/common/expression/ColumnRef.java b/src/main/java/org/tikv/common/expression/ColumnRef.java
index 0a6ed6e4b0..61746cd2e1 100644
--- a/src/main/java/org/tikv/common/expression/ColumnRef.java
+++ b/src/main/java/org/tikv/common/expression/ColumnRef.java
@@ -123,9 +123,9 @@ public class ColumnRef extends Expression {
   @Override
   public int hashCode() {
     if (isResolved()) {
-      return Objects.hash(this.name, this.dataType);
+      return Objects.hash(this.name.toLowerCase(), this.dataType);
     } else {
-      return Objects.hashCode(name);
+      return Objects.hashCode(name.toLowerCase());
     }
   }