diff --git a/src/share/parameter/ob_parameter_seed.ipp b/src/share/parameter/ob_parameter_seed.ipp
index 982b073f95..c770c797b6 100644
--- a/src/share/parameter/ob_parameter_seed.ipp
+++ b/src/share/parameter/ob_parameter_seed.ipp
@@ -1604,7 +1604,7 @@ ERRSIM_DEF_STR(errsim_transfer_backfill_server_addr, OB_CLUSTER_PARAMETER, "",
 DEF_BOOL(_ob_enable_direct_load, OB_CLUSTER_PARAMETER, "True",
          "Enable or disable direct path load",
          ObParameterAttr(Section::OBSERVER, Source::DEFAULT, EditLevel::DYNAMIC_EFFECTIVE));
-DEF_BOOL(_px_join_skew_handling, OB_TENANT_PARAMETER, "True",
+DEF_BOOL(_px_join_skew_handling, OB_TENANT_PARAMETER, "False",
         "enables skew handling for parallel joins. The  default value is True.",
         ObParameterAttr(Section::OBSERVER, Source::DEFAULT, EditLevel::DYNAMIC_EFFECTIVE));
 DEF_INT(_px_join_skew_minfreq, OB_TENANT_PARAMETER, "30", "[1,100]",
diff --git a/src/sql/optimizer/ob_log_plan.cpp b/src/sql/optimizer/ob_log_plan.cpp
index cdbdfe2c8b..605f57911e 100644
--- a/src/sql/optimizer/ob_log_plan.cpp
+++ b/src/sql/optimizer/ob_log_plan.cpp
@@ -4824,16 +4824,16 @@ void ObLogPlan::compute_null_distribution_info(const ObJoinType &join_type,
         right_exch_info.null_row_dist_method_ = ObNullDistributeMethod::DROP;
         break;
       case ObJoinType::LEFT_OUTER_JOIN:
-        left_exch_info.null_row_dist_method_ = ObNullDistributeMethod::RANDOM;
+        left_exch_info.null_row_dist_method_ = ObNullDistributeMethod::NONE;
         right_exch_info.null_row_dist_method_ = ObNullDistributeMethod::DROP;
         break;
       case ObJoinType::RIGHT_OUTER_JOIN:
         left_exch_info.null_row_dist_method_ = ObNullDistributeMethod::DROP;
-        right_exch_info.null_row_dist_method_ = ObNullDistributeMethod::RANDOM;
+        right_exch_info.null_row_dist_method_ = ObNullDistributeMethod::NONE;
         break;
       case ObJoinType::FULL_OUTER_JOIN:
-        left_exch_info.null_row_dist_method_ = ObNullDistributeMethod::RANDOM;
-        right_exch_info.null_row_dist_method_ = ObNullDistributeMethod::RANDOM;
+        left_exch_info.null_row_dist_method_ = ObNullDistributeMethod::NONE;
+        right_exch_info.null_row_dist_method_ = ObNullDistributeMethod::NONE;
         break;
       default:
         left_exch_info.null_row_dist_method_ = ObNullDistributeMethod::NONE;