diff --git a/src/sql/engine/window_function/ob_window_function_op.cpp b/src/sql/engine/window_function/ob_window_function_op.cpp
index d97439681f..8629d59610 100644
--- a/src/sql/engine/window_function/ob_window_function_op.cpp
+++ b/src/sql/engine/window_function/ob_window_function_op.cpp
@@ -3387,114 +3387,117 @@ int ObWindowFunctionOp::process_child_batch(
   ObEvalCtx::BatchInfoScopeGuard guard(eval_ctx_);
   guard.set_batch_size(child_brs->size_);
   guard.set_batch_idx(batch_idx);
-  //When find a big partition, store remaining rows of the batch to %remain row store
-  RowsStore &current = *input_rows_.cur_;
-  RowsStore &processed = *input_rows_.processed_;
-  RowsStore &remain = processed.is_empty() ? processed : current;
-  const bool need_split_store = processed.is_empty();
   bool found_next_part = false;
   OZ(check_stack_overflow());
 
-  while (OB_SUCC(ret) && !found_next_part) {
-    // handle current batch
+  while (OB_SUCC(ret) && !found_next_part) { // handle current batch
     const ObBitVector &skip = *child_brs->skip_;
-    while (OB_SUCC(ret) && row_idx < child_brs->size_ && !found_next_part) {
-      bool same_part = false;
-      guard.set_batch_idx(row_idx);
-      int64_t row_cnt_inc = 0;
-      if (skip.contain(row_idx)) {
-        ++row_idx;
-        continue;
-      } else if (OB_FAIL(check_same_partition(*first, same_part))) {
-        LOG_WARN("check same partition failed", K(ret));
-      } else if (!same_part) {
-        if (OB_FAIL(check_wf_same_partition(end))) {
-          LOG_WARN("check wf same partition failed", K(ret));
-        } else if (OB_FAIL(found_part_end(end, input_rows_.cur_))) {
-          LOG_WARN("found_part_end failed", K(ret));
-        } else if (end != wf_list_.get_header()) {
-          if (OB_FAIL(found_new_part(false))) {
-            LOG_WARN("save partition by exprs failed", K(ret));
-          } else if (OB_FAIL(current.add_row_with_index(row_idx, get_all_expr(),
-                                                        &eval_ctx_, NULL, false))) {
-            LOG_WARN("add row to rows_store failed", K(ret));
+    bool need_loop_until_child_brs_end = true;
+    while (OB_SUCC(ret) && need_loop_until_child_brs_end) {
+      need_loop_until_child_brs_end = false;
+      found_next_part = false;
+      RowsStore &current = *input_rows_.cur_;
+      RowsStore &processed = *input_rows_.processed_;
+      // When find a big partition, store remaining rows of the batch to %remain row store
+      RowsStore &remain = processed.is_empty() ? processed : current;
+      const bool need_split_store = processed.is_empty();
+      while (OB_SUCC(ret) && row_idx < child_brs->size_ && !found_next_part) {
+        bool same_part = false;
+        guard.set_batch_idx(row_idx);
+        int64_t row_cnt_inc = 0;
+        if (skip.contain(row_idx)) {
+          ++row_idx;
+          continue;
+        } else if (OB_FAIL(check_same_partition(*first, same_part))) {
+          LOG_WARN("check same partition failed", K(ret));
+        } else if (!same_part) {
+          if (OB_FAIL(check_wf_same_partition(end))) {
+            LOG_WARN("check wf same partition failed", K(ret));
+          } else if (OB_FAIL(found_part_end(end, input_rows_.cur_))) {
+            LOG_WARN("found_part_end failed", K(ret));
+          } else if (end != wf_list_.get_header()) {
+            if (OB_FAIL(found_new_part(false))) {
+              LOG_WARN("save partition by exprs failed", K(ret));
+            } else if (OB_FAIL(current.add_row_with_index(row_idx, get_all_expr(),
+                                                          &eval_ctx_, NULL, false))) {
+              LOG_WARN("add row to rows_store failed", K(ret));
+            } else {
+              // the biggest part end : remain row_cnt_ + 0, store_row_cnt_ + 1
+              // other parts end : after compute_wf_values, current row_cnt_ + 1, store_row_cnt_ + 1
+              row_cnt_inc = 1;
+            }
           } else {
-            // the biggest part end : remain row_cnt_ + 0, store_row_cnt_ + 1
-            // other parts end : after compute_wf_values, current row_cnt_ + 1, store_row_cnt_ + 1
-            row_cnt_inc = 1;
+            found_next_part = true;
+            if (OB_FAIL(found_new_part(false))) {
+              LOG_WARN("save partition by exprs failed", K(ret));
+            } else if (OB_FAIL(remain.add_row_with_index(row_idx, get_all_expr(), &eval_ctx_,
+                                                  NULL, false))) {
+              LOG_WARN("add row to rows_store failed", K(ret));
+            }
           }
-        } else {
-          found_next_part = true;
-          if (OB_FAIL(found_new_part(false))) {
+          if (OB_FAIL(ret)) {
+          } else if (OB_FAIL(compute_wf_values(end, check_times))) {
+            LOG_WARN("compute wf values failed", K(ret));
+          } else if (OB_FAIL(save_part_first_row_idx())) {
             LOG_WARN("save partition by exprs failed", K(ret));
-          } else if (OB_FAIL(remain.add_row_with_index(row_idx, get_all_expr(), &eval_ctx_,
-                                                NULL, false))) {
+          } else {
+            // compute_wf_values will use current.row_cnt to decide which rows need to compute
+            // so add row_cnt_inc to current.row_cnt after compute_wf_values
+            current.row_cnt_ += row_cnt_inc;
+          }
+        } else { // same part
+          if (MY_SPEC.is_participator()) {
+            MY_SPEC.wf_aggr_status_expr_->locate_datum_for_write(eval_ctx_).set_int(last_aggr_status_);
+          }
+          if (OB_FAIL(current.add_row_with_index(row_idx, get_all_expr(), &eval_ctx_))) {
             LOG_WARN("add row to rows_store failed", K(ret));
           }
         }
-        if (OB_FAIL(ret)) {
-        } else if (OB_FAIL(compute_wf_values(end, check_times))) {
-          LOG_WARN("compute wf values failed", K(ret));
-        } else if (OB_FAIL(save_part_first_row_idx())) {
-          LOG_WARN("save partition by exprs failed", K(ret));
-        } else {
-          // compute_wf_values will use current.row_cnt to decide which rows need to compute
-          // so add row_cnt_inc to current.row_cnt after compute_wf_values
-          current.row_cnt_ += row_cnt_inc;
-        }
-      } else { // same part
-        if (MY_SPEC.is_participator()) {
-          MY_SPEC.wf_aggr_status_expr_->locate_datum_for_write(eval_ctx_).set_int(last_aggr_status_);
-        }
-        if (OB_FAIL(current.add_row_with_index(row_idx, get_all_expr(), &eval_ctx_))) {
-          LOG_WARN("add row to rows_store failed", K(ret));
+        if (OB_SUCC(ret) && !found_next_part) {
+          ++row_idx;
         }
       }
-      if (OB_SUCC(ret) && !found_next_part) {
-        ++row_idx;
-      }
-    }
-
-    if (OB_SUCC(ret)) {
-      if (found_next_part) {
-        if (need_split_store) {
-          // switch %cur_ and %processed_ row store if necessary
-          // %cur_ always be rows store we are computing.
-          // And rows in %processed_ row store are all computed and ready to output.
-          // swap $cur_ and $processed_ row store
-          foreach_stores([](Stores &s){ std::swap(s.cur_, s.processed_); return OB_SUCCESS; });
-          if (MY_SPEC.range_dist_parallel_ && !first_part_saved_) {
-            first_part_saved_ = true;
-            foreach_stores([](Stores &s){ std::swap(s.first_, s.processed_); return OB_SUCCESS; });
+      if (OB_SUCC(ret)) {
+        if (found_next_part) {
+          if (need_split_store) {
+            // switch %cur_ and %processed_ row store if necessary
+            // %cur_ always be rows store we are computing.
+            // And rows in %processed_ row store are all computed and ready to output.
+            // swap $cur_ and $processed_ row store
+            foreach_stores([](Stores &s){ std::swap(s.cur_, s.processed_); return OB_SUCCESS; });
+            if (MY_SPEC.range_dist_parallel_ && !first_part_saved_) {
+              first_part_saved_ = true;
+              foreach_stores([](Stores &s){ std::swap(s.first_, s.processed_); return OB_SUCCESS; });
+            }
           }
-        }
-        ++row_idx;
-        ++remain.row_cnt_;
-        if (need_split_store && OB_FAIL(save_part_first_row_idx())) {
-          LOG_WARN("save partition by exprs failed", K(ret));
-        } else if (OB_FAIL(process_child_batch(row_idx, child_brs, check_times))) {
-          LOG_WARN("add row to rows_store failed", K(ret));
-        }
-      } else if (!child_iter_end_) {
-        if (need_split_store) { // need_split_store is true means we have not found next part ever
-          if (OB_FAIL(get_next_batch_from_child(batch_size, child_brs))) {
-            LOG_WARN("get child next batch failed", K(ret));
+          ++row_idx;
+          ++remain.row_cnt_;
+          if (need_split_store && OB_FAIL(save_part_first_row_idx())) {
+            LOG_WARN("save partition by exprs failed", K(ret));
+          } else { // need to deal with remain rows in this child_brs after found new part
+            need_loop_until_child_brs_end = true;
+          }
+        } else if (!child_iter_end_) {
+          if (need_split_store) { // need_split_store is true means we have not found next part ever
+            if (OB_FAIL(get_next_batch_from_child(batch_size, child_brs))) {
+              LOG_WARN("get child next batch failed", K(ret));
+            } else {
+              child_iter_end_ = child_brs->end_;
+              row_idx = 0;
+              guard.set_batch_size(child_brs->size_);
+            }
           } else {
-            child_iter_end_ = child_brs->end_;
-            row_idx = 0;
-            guard.set_batch_size(child_brs->size_);
+            found_next_part = true;
+            current.row_cnt_ = wf_list_.get_last()->part_first_row_idx_;
           }
-        } else {
+        } else { // child_iter_end_
           found_next_part = true;
-          current.row_cnt_ = wf_list_.get_last()->part_first_row_idx_;
-        }
-      } else { // child_iter_end_
-        found_next_part = true;
-        // add aggr result row for the last part
-        if (OB_FAIL(found_part_end(wf_list_.get_header(), input_rows_.cur_))) {
-          LOG_WARN("found_part_end failed", K(ret), K(last_aggr_status_));
-        } else if (OB_FAIL(compute_wf_values(wf_list_.get_header(), check_times))) {
-          LOG_WARN("compute wf values failed", K(ret));
+          // add aggr result row for the last part
+          if (OB_FAIL(found_part_end(wf_list_.get_header(), input_rows_.cur_))) {
+            LOG_WARN("found_part_end failed", K(ret), K(last_aggr_status_));
+          } else if (OB_FAIL(compute_wf_values(wf_list_.get_header(), check_times))) {
+            LOG_WARN("compute wf values failed", K(ret));
+          }
         }
       }
     }