diff --git a/src/storage/access/ob_sample_filter.cpp b/src/storage/access/ob_sample_filter.cpp
index 56a966118..fdc6a6c6e 100644
--- a/src/storage/access/ob_sample_filter.cpp
+++ b/src/storage/access/ob_sample_filter.cpp
@@ -175,6 +175,9 @@ int ObSampleFilterExecutor::build_row_id_handle(
   } else if (nullptr != index_row_id_handle_) {
     MEMSET(static_cast<void *>(index_row_id_handle_), 0, sizeof(ObIndexRowIdHandle) * index_handle_max_cnt);
     MEMSET(static_cast<void *>(data_row_id_handle_), 0, sizeof(int64_t) * data_handle_max_cnt);
+    row_id_handle_cap_ = height;
+    index_prefetch_depth_ = index_handle_cnt;
+    data_prefetch_depth_ = data_handle_cnt;
   } else if (OB_ISNULL(buf = allocator_->alloc(sizeof(ObIndexRowIdHandle) * index_handle_max_cnt + sizeof(int64_t) * data_handle_max_cnt))) {
     ret = OB_ALLOCATE_MEMORY_FAILED;
     LOG_WARN("Failed to alloc memory for index_row_id_handle and data_row_id_handle", K(ret), K(index_handle_max_cnt), K(data_handle_max_cnt));
diff --git a/src/storage/access/ob_sample_filter.h b/src/storage/access/ob_sample_filter.h
index b6fa4169d..c7eb0e14f 100644
--- a/src/storage/access/ob_sample_filter.h
+++ b/src/storage/access/ob_sample_filter.h
@@ -103,7 +103,7 @@ public:
     count_ = std::floor(static_cast<double>((interval_id_ + 1) * interval_length_) * percent_ / 100)
               - std::floor(static_cast<double>(interval_id_ * interval_length_) * percent_ / 100);
     uint64_t hash_value = murmurhash(&interval_id_, sizeof(interval_id_), static_cast<uint64_t>(seed_));
-    uint64_t offset = interval_length_ <= count_ ? 0 : hash_value % (interval_length_ - count_);
+    uint64_t offset = interval_length_ <= count_ ? 0 : hash_value % (interval_length_ - count_ + 1);
     left_ = static_cast<int64_t>(interval_length_ * interval_id_ + offset) + start_;
     right_ = left_ + count_ - 1;
   }
diff --git a/unittest/storage/test_sample_filter.cpp b/unittest/storage/test_sample_filter.cpp
index 17bda3a5c..6c0e249e0 100644
--- a/unittest/storage/test_sample_filter.cpp
+++ b/unittest/storage/test_sample_filter.cpp
@@ -67,10 +67,10 @@ public:
 
 TEST_F(ObRowSampleFilterTest, test_filter_single_row)
 {
-  bool result[20] = {0, 0, 1, 0,
-                     1, 1, 0, 0,
+  bool result[20] = {0, 1, 0, 0,
+                     0, 0, 1, 1,
                      0, 0, 1, 0,
-                     1, 1, 0, 0,
+                     0, 1, 1, 0,
                      1, 1, 0, 0};
   bool filtered = false;
   for(int row_num = 0; row_num < 20; row_num++) {
@@ -82,18 +82,18 @@ TEST_F(ObRowSampleFilterTest, test_filter_single_row)
 TEST_F(ObRowSampleFilterTest, test_filter_range)
 {
   ObMicroIndexInfo index_info;
-  check_sample_range(0, 1, index_info, true);
-  check_sample_range(3, 3, index_info, true);
-  check_sample_range(6, 9, index_info, true);
-  check_sample_range(11, 11, index_info, true);
-  check_sample_range(14, 15, index_info, true);
+  check_sample_range(0, 0, index_info, true);
+  check_sample_range(2, 5, index_info, true);
+  check_sample_range(8, 9, index_info, true);
+  check_sample_range(11, 12, index_info, true);
+  check_sample_range(15, 15, index_info, true);
   check_sample_range(18, 19, index_info, true);
 
   check_sample_range(0, 2, index_info, false);
   check_sample_range(0, 4, index_info, false);
-  check_sample_range(4, 4, index_info, false);
+  check_sample_range(5, 6, index_info, false);
   check_sample_range(5, 9, index_info, false);
-  check_sample_range(6, 10, index_info, false);
+  check_sample_range(7, 9, index_info, false);
   check_sample_range(12, 13, index_info, false);
   check_sample_range(15, 16, index_info, false);
   check_sample_range(17, 17, index_info, false);
@@ -102,10 +102,10 @@ TEST_F(ObRowSampleFilterTest, test_filter_range)
 
 TEST_F(ObRowSampleFilterTest, test_set_sample_bitmap)
 {
-  bool result[20] = {0, 0, 1, 0,
-                     1, 1, 0, 0,
+  bool result[20] = {0, 1, 0, 0,
+                     0, 0, 1, 1,
                      0, 0, 1, 0,
-                     1, 1, 0, 0,
+                     0, 1, 1, 0,
                      1, 1, 0, 0};
   ObBitmap *result_bitmap = nullptr;
   ASSERT_EQ(OB_SUCCESS, sample_executor_->init_bitmap(20, result_bitmap));