diff --git a/src/sql/engine/expr/ob_expr_soundex.cpp b/src/sql/engine/expr/ob_expr_soundex.cpp
index 2a6420908a..be7379cbd6 100644
--- a/src/sql/engine/expr/ob_expr_soundex.cpp
+++ b/src/sql/engine/expr/ob_expr_soundex.cpp
@@ -101,6 +101,7 @@ int ObExprSoundex::calc_result_type1(
       res_type = ObVarcharType;
       res_length = OB_MAX_BINARY_LENGTH;
       res_cs_type = type_ctx.get_coll_type();
+      raw_expr->set_extra(static_cast<uint64_t>(res_cs_type));
     }
   }
   if (OB_SUCC(ret)) {