diff --git a/src/sql/engine/aggregate/ob_exec_hash_struct_vec.h b/src/sql/engine/aggregate/ob_exec_hash_struct_vec.h
index 106c6940d0..6ccc7192fd 100644
--- a/src/sql/engine/aggregate/ob_exec_hash_struct_vec.h
+++ b/src/sql/engine/aggregate/ob_exec_hash_struct_vec.h
@@ -816,7 +816,7 @@ public:
       SQL_ENG_LOG(WARN, "invalid null buckets", K(ret), K(buckets_));
     }
     for (int64_t i = 0; OB_SUCC(ret) && i < get_bucket_num(); i++) {
-      if (OB_FAIL(cb(buckets_->at(i).get_hash()))) {
+      if (buckets_->at(i).is_valid() && OB_FAIL(cb(buckets_->at(i).get_hash()))) {
         SQL_ENG_LOG(WARN, "call back failed", K(ret));
       }
     }
diff --git a/src/sql/engine/aggregate/ob_hash_groupby_op.cpp b/src/sql/engine/aggregate/ob_hash_groupby_op.cpp
index 489e501e8b..f047aa27da 100644
--- a/src/sql/engine/aggregate/ob_hash_groupby_op.cpp
+++ b/src/sql/engine/aggregate/ob_hash_groupby_op.cpp
@@ -449,6 +449,7 @@ int ObHashGroupByOp::inner_rescan()
 {
   int ret = OB_SUCCESS;
   reset();
+  llc_est_.reset();
   if (OB_FAIL(ObGroupByOp::inner_rescan())) {
     LOG_WARN("failed to rescan", K(ret));
   } else {
diff --git a/src/sql/engine/aggregate/ob_hash_groupby_vec_op.cpp b/src/sql/engine/aggregate/ob_hash_groupby_vec_op.cpp
index b20eceb49d..9eb497d5d7 100644
--- a/src/sql/engine/aggregate/ob_hash_groupby_vec_op.cpp
+++ b/src/sql/engine/aggregate/ob_hash_groupby_vec_op.cpp
@@ -377,6 +377,7 @@ int ObHashGroupByVecOp::inner_rescan()
 {
   int ret = OB_SUCCESS;
   reset(true);
+  llc_est_.reset();
   if (OB_FAIL(ObGroupByVecOp::inner_rescan())) {
     LOG_WARN("failed to rescan", K(ret));
   } else {
@@ -977,6 +978,10 @@ int ObHashGroupByVecOp::inner_get_next_batch(const int64_t max_row_cnt)
         bypass_ctrl_.reset_state();
         by_pass_vec_holder_.restore();
         calc_avg_group_mem();
+        if (llc_est_.enabled_ && llc_est_.est_cnt_ != agged_group_cnt_) {
+          ret = OB_ERR_UNEXPECTED;
+          LOG_WARN("unexpected est_cnt number", K(ret), K(agged_group_cnt_), K(agged_row_cnt_), K(llc_est_.est_cnt_));
+        }
       }
       if (!bypass_ctrl_.by_passing()) {
         if (OB_FAIL(by_pass_restart_round())) {
@@ -1226,18 +1231,8 @@ int ObHashGroupByVecOp::load_data_batch(int64_t max_row_cnt)
   } // while end
 
   row_store_iter.reset();
-  if (OB_SUCC(ret) && llc_est_.enabled_) {
-    if (local_group_rows_.is_sstr_aggr_valid()) {
-      llc_est_.enabled_ = false;// do not need llc, ndv must less then 65535
-    } else {
-      AddLlcCallback cb_func(&llc_est_);
-      if (OB_FAIL(local_group_rows_.foreach_bucket_hash(cb_func))) {
-        LOG_WARN("add hash val from local_group_rows_ to llc_est_ failed", K(ret));
-      } else {
-        llc_est_.est_cnt_ += agged_row_cnt_;
-        LOG_TRACE("llc map succ to add hash val from insert state", K(ret), K(llc_est_.est_cnt_), K(agged_row_cnt_), K(agged_group_cnt_));
-      }
-    }
+  if (OB_SUCC(ret) && llc_est_.enabled_ && local_group_rows_.is_sstr_aggr_valid()) {
+    llc_est_.enabled_ = false;// do not need llc, ndv must less then 65535
   }
   if (OB_FAIL(ret)) {
   } else if (NULL == cur_part && !use_distinct_data_ && OB_FAIL(finish_insert_distinct_data())) {
@@ -1591,6 +1586,13 @@ int ObHashGroupByVecOp::batch_process_duplicate_data(
       }
       force_check_dump = false;
       new_group_cnt = agged_group_cnt_ - orign_agged_group_cnt;
+      if (OB_SUCC(ret) && llc_est_.enabled_) {
+        for (int64_t i = 0; OB_SUCC(ret) && i < child_brs.size_; i++) {
+          if (batch_new_rows_[i]) {
+            llc_add_value(hash_vals_[i]);
+          }
+        }
+      }
       if (OB_SUCC(ret) && 0 < new_group_cnt) {
         int64_t curr_cnt = 0;
         for (int64_t i = 0; OB_SUCC(ret) && i < child_brs.size_; i++) {
@@ -1866,6 +1868,13 @@ int ObHashGroupByVecOp::group_child_batch_rows(const ObCompactRow **store_rows,
     }
     force_check_dump = false;
     new_groups = agged_group_cnt_ - orign_agged_group_cnt;
+    if (OB_SUCC(ret) && llc_est_.enabled_) {
+      for (int64_t i = 0; OB_SUCC(ret) && i < child_brs.size_; i++) {
+        if (batch_new_rows_[i]) {
+          llc_add_value(hash_vals_[i]);
+        }
+      }
+    }
     if (OB_SUCC(ret) && new_groups > 0) {
       int64_t curr_cnt = 0;
       for (int64_t i = 0; OB_SUCC(ret) && i < child_brs.size_; ++i) {
diff --git a/src/sql/engine/aggregate/ob_hash_groupby_vec_op.h b/src/sql/engine/aggregate/ob_hash_groupby_vec_op.h
index e6ec734b6f..731f5e9a1e 100644
--- a/src/sql/engine/aggregate/ob_hash_groupby_vec_op.h
+++ b/src/sql/engine/aggregate/ob_hash_groupby_vec_op.h
@@ -47,21 +47,6 @@ public:
   static constexpr const double GLOBAL_BOUND_RATIO_ = 0.8;
 };
 
-class AddLlcCallback
-{
-public:
-  explicit AddLlcCallback(LlcEstimate *llc_est_ptr) { llc_est_ptr_ = llc_est_ptr; }
-  AddLlcCallback() = delete;
-  virtual ~AddLlcCallback() = default;
-  int operator()(uint64_t hash_val) {
-    // for performance, do not check if llc_est_ptr_ is NULL ptr or not
-    ObAggregateProcessor::llc_add_value(hash_val, llc_est_ptr_->llc_map_);
-    return OB_SUCCESS;
-  }
-private:
-  LlcEstimate *llc_est_ptr_;
-};
-
 struct ObGroupByDupColumnPairVec
 {
   OB_UNIS_VERSION_V(1);