diff --git a/src/sql/optimizer/ob_join_order.cpp b/src/sql/optimizer/ob_join_order.cpp
index e93f92674..e884b39b1 100644
--- a/src/sql/optimizer/ob_join_order.cpp
+++ b/src/sql/optimizer/ob_join_order.cpp
@@ -3515,12 +3515,10 @@ int JoinPath::re_est_cost(sql::Path* path, double need_row_count, double& cost)
   if (OB_ISNULL(path)) {
     ret = OB_ERR_UNEXPECTED;
     LOG_WARN("unexpect null path", K(ret));
-  } else if (ACCESS == path->path_type_ &&
-             OB_FAIL(re_est_access_cost(static_cast<AccessPath*>(path), need_row_count, cost))) {
-    LOG_WARN("failed to est access cost", K(ret));
-  } else if (SUBQUERY == path->path_type_ &&
-             OB_FAIL(re_est_subquery_cost(static_cast<SubQueryPath*>(path), need_row_count, cost))) {
-    LOG_WARN("failed to est subquery cost", K(ret));
+  } else if (ACCESS == path->path_type_) {
+    ret = re_est_access_cost(static_cast<AccessPath*>(path), need_row_count, cost);
+  } else if (SUBQUERY == path->path_type_) {
+    ret = re_est_subquery_cost(static_cast<SubQueryPath*>(path), need_row_count, cost);
   } else {
     cost = path->cost_;
   }
@@ -3570,11 +3568,6 @@ int JoinPath::re_est_access_cost(AccessPath* path, double need_row_count, double
                      cost,
                      index_back_cost))) {
         LOG_WARN("failed to estimate cost", K(ret));
-      } else {
-        path->cost_ = cost;
-        path->op_cost_ = cost;
-        path->inner_row_count_ = need_row_count;
-        path->output_row_count_ = need_row_count;
       }
     } else {
       cost = path->cost_;
diff --git a/src/sql/rewrite/ob_transform_rule.cpp b/src/sql/rewrite/ob_transform_rule.cpp
index 640b0e29f..4a5f895f1 100644
--- a/src/sql/rewrite/ob_transform_rule.cpp
+++ b/src/sql/rewrite/ob_transform_rule.cpp
@@ -167,7 +167,7 @@ int ObTransformRule::accept_transform(
     LOG_WARN("failed to evaluate cost for the origin stmt", K(ret));
   }
   if (OB_SUCC(ret)) {
-    if (trans_stmt_cost < stmt_cost_) {
+    if (trans_stmt_cost < stmt_cost_ * COST_BASE_TRANSFORM_THRESHOLD) {
       LOG_TRACE("accept transform because the cost is decreased", K_(stmt_cost), K(trans_stmt_cost));
       stmt = trans_stmt;
       stmt_cost_ = trans_stmt_cost;
diff --git a/src/sql/rewrite/ob_transform_rule.h b/src/sql/rewrite/ob_transform_rule.h
index ed278b803..af2813c28 100644
--- a/src/sql/rewrite/ob_transform_rule.h
+++ b/src/sql/rewrite/ob_transform_rule.h
@@ -129,6 +129,7 @@ struct ObParentDMLStmt {
 
 class ObTransformRule {
   public:
+  static constexpr const double COST_BASE_TRANSFORM_THRESHOLD = 0.999;
   static const int64_t TRANSFORMER_DEFAULT_MAX_RECURSIVE_LEVEL = 150;
   static const uint64_t ALL_TRANSFORM_RULES = TRANSFORM_TYPE_COUNT_PLUS_ONE - 1;
   static const uint64_t ALL_HEURISTICS_RULES = SIMPLIFY | ANYALL | AGGR | ELIMINATE_OJ | VIEW_MERGE | WHERE_SQ_PULL_UP |
diff --git a/unittest/sql/optimizer/test_optimizer_default_stat.result b/unittest/sql/optimizer/test_optimizer_default_stat.result
index b54fd8740..2cf396947 100644
--- a/unittest/sql/optimizer/test_optimizer_default_stat.result
+++ b/unittest/sql/optimizer/test_optimizer_default_stat.result
@@ -9476,50 +9476,48 @@ Outputs & filters:
 
 SQL: select * from t4,t4 t5 where t4.c1 in (select t7.c1 from t7,t8); 
 
-=================================================================
-|ID|OPERATOR                      |NAME |EST. ROWS  |COST       |
------------------------------------------------------------------
-|0 |NESTED-LOOP JOIN CARTESIAN    |     |15504908587|11299759339|
-|1 | NESTED-LOOP JOIN             |     |155050     |3869186    |
-|2 |  TABLE SCAN                  |t4   |100000     |64066      |
-|3 |  SUBPLAN SCAN                |VIEW2|1          |38         |
-|4 |   LIMIT                      |     |1          |38         |
-|5 |    NESTED-LOOP JOIN CARTESIAN|     |1          |37         |
-|6 |     TABLE GET                |t7   |1          |36         |
-|7 |     TABLE SCAN               |t8   |100000     |59654      |
-|8 | MATERIAL                     |     |100000     |119192     |
-|9 |  TABLE SCAN                  |t5   |100000     |64066      |
-=================================================================
+===============================================================
+|ID|OPERATOR                      |NAME |EST. ROWS |COST      |
+---------------------------------------------------------------
+|0 |NESTED-LOOP JOIN CARTESIAN    |     |9900000000|7216269494|
+|1 | TABLE SCAN                   |t5   |100000    |64066     |
+|2 | MATERIAL                     |     |99000     |3771257   |
+|3 |  NESTED-LOOP SEMI JOIN       |     |99000     |3716682   |
+|4 |   TABLE SCAN                 |t4   |100000    |64066     |
+|5 |   SUBPLAN SCAN               |VIEW1|1         |36        |
+|6 |    NESTED-LOOP JOIN CARTESIAN|     |1         |36        |
+|7 |     TABLE GET                |t7   |1         |36        |
+|8 |     TABLE SCAN               |t8   |100000    |59654     |
+===============================================================
 
 Outputs & filters: 
 -------------------------------------
   0 - output([t4.c1], [t4.c2], [t4.c3], [t5.c1], [t5.c2], [t5.c3]), filter(nil), 
       conds(nil), nl_params_(nil), batch_join=false
-  1 - output([t4.c1], [t4.c2], [t4.c3]), filter(nil), 
+  1 - output([t5.c1], [t5.c2], [t5.c3]), filter(nil), 
+      access([t5.c1], [t5.c2], [t5.c3]), partitions(p0), 
+      is_index_back=false, 
+      range_key([t5.c1], [t5.c2]), range(MIN,MIN ; MAX,MAX)always true
+  2 - output([t4.c1], [t4.c2], [t4.c3]), filter(nil)
+  3 - output([t4.c1], [t4.c2], [t4.c3]), filter(nil), 
       conds(nil), nl_params_([t4.c1]), batch_join=false
-  2 - output([t4.c1], [t4.c2], [t4.c3]), filter(nil), 
+  4 - output([t4.c1], [t4.c2], [t4.c3]), filter(nil), 
       access([t4.c1], [t4.c2], [t4.c3]), partitions(p0), 
       is_index_back=false, 
       range_key([t4.c1], [t4.c2]), range(MIN,MIN ; MAX,MAX)always true
-  3 - output([1]), filter(nil), 
-      access([VIEW2.VIEW1.c1])
-  4 - output([t7.c1]), filter(nil), limit(1), offset(nil)
-  5 - output([t7.c1]), filter(nil), 
-      conds(nil), nl_params_(nil), batch_join=true
+  5 - output([1]), filter(nil), 
+      access([VIEW1.c1])
   6 - output([t7.c1]), filter(nil), 
+      conds(nil), nl_params_(nil), batch_join=true
+  7 - output([t7.c1]), filter(nil), 
       access([t7.c1]), partitions(p0), 
       is_index_back=false, 
       range_key([t7.c1]), range(MIN ; MAX)always true, 
       range_cond([? = t7.c1])
-  7 - output([1]), filter(nil), 
+  8 - output([1]), filter(nil), 
       access([t8.c1]), partitions(p0), 
       is_index_back=false, 
       range_key([t8.c1]), range(MIN ; MAX)always true
-  8 - output([t5.c1], [t5.c2], [t5.c3]), filter(nil)
-  9 - output([t5.c1], [t5.c2], [t5.c3]), filter(nil), 
-      access([t5.c1], [t5.c2], [t5.c3]), partitions(p0), 
-      is_index_back=false, 
-      range_key([t5.c1], [t5.c2]), range(MIN,MIN ; MAX,MAX)always true
 
 *************** Case 273(end)  ************** 
 
diff --git a/unittest/sql/optimizer/test_optimizer_outline.result b/unittest/sql/optimizer/test_optimizer_outline.result
index bfc794ad0..ebd7a4300 100644
--- a/unittest/sql/optimizer/test_optimizer_outline.result
+++ b/unittest/sql/optimizer/test_optimizer_outline.result
@@ -3003,17 +3003,15 @@ SQL: select t20.c1 from t20 join t0 where t0.c1 in (select t7.c1 from t7 join t8
 ========================================================
 |ID|OPERATOR                     |NAME |EST. ROWS|COST |
 --------------------------------------------------------
-|0 |NESTED-LOOP JOIN CARTESIAN   |     |10000    |17490|
-|1 | MERGE SEMI JOIN             |     |100      |10301|
-|2 |  SORT                       |     |100      |198  |
-|3 |   TABLE SCAN                |t0   |100      |90   |
-|4 |  SUBPLAN SCAN               |VIEW1|10000    |8650 |
-|5 |   NESTED-LOOP JOIN CARTESIAN|     |10000    |7270 |
-|6 |    TABLE SCAN               |t7   |100      |88   |
-|7 |    MATERIAL                 |     |100      |106  |
-|8 |     TABLE SCAN              |t8   |100      |88   |
-|9 | MATERIAL                    |     |100      |113  |
-|10|  TABLE SCAN                 |t20  |100      |95   |
+|0 |NESTED-LOOP JOIN CARTESIAN   |     |10000    |10934|
+|1 | NESTED-LOOP SEMI JOIN       |     |100      |3745 |
+|2 |  TABLE SCAN                 |t0   |100      |90   |
+|3 |  SUBPLAN SCAN               |VIEW1|1        |36   |
+|4 |   NESTED-LOOP JOIN CARTESIAN|     |1        |36   |
+|5 |    TABLE GET                |t7   |1        |36   |
+|6 |    TABLE SCAN               |t8   |100      |88   |
+|7 | MATERIAL                    |     |100      |113  |
+|8 |  TABLE SCAN                 |t20  |100      |95   |
 ========================================================
 
 Outputs & filters: 
@@ -3021,21 +3019,19 @@ Outputs & filters:
   0 - output([t20.c1]), filter(nil), 
       conds(nil), nl_params_(nil)
   1 - output([1]), filter(nil), 
-      equal_conds([t0.c1 = VIEW1.c1]), other_conds(nil)
-  2 - output([t0.c1]), filter(nil), sort_keys([t0.c1, ASC])
-  3 - output([t0.c1]), filter(nil), 
+      conds(nil), nl_params_([t0.c1])
+  2 - output([t0.c1]), filter(nil), 
       access([t0.c1]), partitions(p0)
-  4 - output([VIEW1.c1]), filter(nil), 
+  3 - output([1]), filter(nil), 
       access([VIEW1.c1])
-  5 - output([t7.c1]), filter(nil), 
+  4 - output([t7.c1]), filter(nil), 
       conds(nil), nl_params_(nil)
-  6 - output([t7.c1]), filter(nil), 
+  5 - output([t7.c1]), filter(nil), 
       access([t7.c1]), partitions(p0)
-  7 - output([1]), filter(nil)
-  8 - output([1]), filter(nil), 
+  6 - output([1]), filter(nil), 
       access([t8.c1]), partitions(p0)
-  9 - output([t20.c1]), filter(nil)
-  10 - output([t20.c1]), filter(nil), 
+  7 - output([t20.c1]), filter(nil)
+  8 - output([t20.c1]), filter(nil), 
       access([t20.c1]), partitions(p0)
 
 Outline Data:
@@ -3045,11 +3041,12 @@ Outline Data:
       LEADING(@"SEL$1" (("opt.t0"@"SEL$1" "VIEW1"@"SEL$1" )"opt.t20"@"SEL$1" ))
       USE_NL(@"SEL$1" ("opt.t20"@"SEL$1" ))
       USE_NL_MATERIALIZATION(@"SEL$1" ("opt.t20"@"SEL$1" ))
-      USE_MERGE(@"SEL$1" ("VIEW1"@"SEL$1" ))
+      USE_NL(@"SEL$1" ("VIEW1"@"SEL$1" ))
+      NO_USE_NL_MATERIALIZATION(@"SEL$1" ("VIEW1"@"SEL$1" ))
       FULL(@"SEL$1" "opt.t0"@"SEL$1")
       LEADING(@"SEL$2" ("opt.t7"@"SEL$2" "opt.t8"@"SEL$2" ))
       USE_NL(@"SEL$2" ("opt.t8"@"SEL$2" ))
-      USE_NL_MATERIALIZATION(@"SEL$2" ("opt.t8"@"SEL$2" ))
+      NO_USE_NL_MATERIALIZATION(@"SEL$2" ("opt.t8"@"SEL$2" ))
       FULL(@"SEL$2" "opt.t7"@"SEL$2")
       FULL(@"SEL$2" "opt.t8"@"SEL$2")
       FULL(@"SEL$1" "opt.t20"@"SEL$1")
diff --git a/unittest/sql/rewrite/result/test_transformer_plan_after_trans_outline.result b/unittest/sql/rewrite/result/test_transformer_plan_after_trans_outline.result
index 77c2585a6..3408589cf 100644
--- a/unittest/sql/rewrite/result/test_transformer_plan_after_trans_outline.result
+++ b/unittest/sql/rewrite/result/test_transformer_plan_after_trans_outline.result
@@ -2472,34 +2472,30 @@ Outline Data:
 
 ***************   Case 77   ***************
 SQL: SELECT c1 FROM pullup1 WHERE c1 IN (SELECT pullup2.pk FROM pullup2, pullup3); 
-===============================================================
-|ID|OPERATOR                    |NAME         |EST. ROWS|COST |
----------------------------------------------------------------
-|0 |MERGE SEMI JOIN             |             |100      |10265|
-|1 | SORT                       |             |100      |198  |
-|2 |  TABLE SCAN                |pullup1      |100      |90   |
-|3 | SUBPLAN SCAN               |VIEW1        |10000    |8615 |
-|4 |  NESTED-LOOP JOIN CARTESIAN|             |10000    |7235 |
-|5 |   TABLE SCAN               |pullup2      |100      |88   |
-|6 |   MATERIAL                 |             |100      |71   |
-|7 |    TABLE SCAN              |pullup3(uniq)|100      |52   |
-===============================================================
+==============================================================
+|ID|OPERATOR                    |NAME         |EST. ROWS|COST|
+--------------------------------------------------------------
+|0 |NESTED-LOOP SEMI JOIN       |             |100      |3745|
+|1 | TABLE SCAN                 |pullup1      |100      |90  |
+|2 | SUBPLAN SCAN               |VIEW1        |1        |36  |
+|3 |  NESTED-LOOP JOIN CARTESIAN|             |1        |36  |
+|4 |   TABLE GET                |pullup2      |1        |36  |
+|5 |   TABLE SCAN               |pullup3(uniq)|100      |52  |
+==============================================================
 
 Outputs & filters: 
 -------------------------------------
   0 - output([pullup1.c1]), filter(nil), 
-      equal_conds([pullup1.c1 = VIEW1.pk]), other_conds(nil)
-  1 - output([pullup1.c1]), filter(nil), sort_keys([pullup1.c1, ASC])
-  2 - output([pullup1.c1]), filter(nil), 
+      conds(nil), nl_params_([pullup1.c1])
+  1 - output([pullup1.c1]), filter(nil), 
       access([pullup1.c1]), partitions(p0)
-  3 - output([VIEW1.pk]), filter(nil), 
+  2 - output([1]), filter(nil), 
       access([VIEW1.pk])
-  4 - output([pullup2.pk]), filter(nil), 
+  3 - output([pullup2.pk]), filter(nil), 
       conds(nil), nl_params_(nil)
-  5 - output([pullup2.pk]), filter(nil), 
+  4 - output([pullup2.pk]), filter(nil), 
       access([pullup2.pk]), partitions(p0)
-  6 - output([1]), filter(nil)
-  7 - output([1]), filter(nil), 
+  5 - output([1]), filter(nil), 
       access([pullup3.uniq_c2]), partitions(p0)
 
 Outline Data:
@@ -2507,11 +2503,12 @@ Outline Data:
   /*+
       BEGIN_OUTLINE_DATA
       LEADING(@"SEL$1" ("opt.pullup1"@"SEL$1" "VIEW1"@"SEL$1" ))
-      USE_MERGE(@"SEL$1" ("VIEW1"@"SEL$1" ))
+      USE_NL(@"SEL$1" ("VIEW1"@"SEL$1" ))
+      NO_USE_NL_MATERIALIZATION(@"SEL$1" ("VIEW1"@"SEL$1" ))
       FULL(@"SEL$1" "opt.pullup1"@"SEL$1")
       LEADING(@"SEL$2" ("opt.pullup2"@"SEL$2" "opt.pullup3"@"SEL$2" ))
       USE_NL(@"SEL$2" ("opt.pullup3"@"SEL$2" ))
-      USE_NL_MATERIALIZATION(@"SEL$2" ("opt.pullup3"@"SEL$2" ))
+      NO_USE_NL_MATERIALIZATION(@"SEL$2" ("opt.pullup3"@"SEL$2" ))
       FULL(@"SEL$2" "opt.pullup2"@"SEL$2")
       INDEX(@"SEL$2" "opt.pullup3"@"SEL$2" "uniq")
       END_OUTLINE_DATA