diff --git a/lib/execution/executors/executor_test/skiplist_index_executor_test.go b/lib/execution/executors/executor_test/skiplist_index_executor_test.go
index e7cf2e87..18a1ce1c 100644
--- a/lib/execution/executors/executor_test/skiplist_index_executor_test.go
+++ b/lib/execution/executors/executor_test/skiplist_index_executor_test.go
@@ -1071,7 +1071,7 @@ func InnerTestParallelTxnsQueryingIndexUsedColumns[T int32 | float32 | string](t
 					return
 				}
 				common.ShPrintf(common.DEBUGGING, "Select(success) op start.\n")
-				diffToMakeNoExist := int32(10)
+				//diffToMakeNoExist := int32(10)
 			rangeSelectRetry:
 				var rangeStartKey = samehada_util.ChoiceKeyFromMap(insVals)
 				var rangeEndKey = samehada_util.ChoiceKeyFromMap(insVals)
@@ -1079,8 +1079,10 @@ func InnerTestParallelTxnsQueryingIndexUsedColumns[T int32 | float32 | string](t
 					goto rangeSelectRetry
 				}
 				insValsMutex.RUnlock()
-				// get 0-8 value
-				tmpRand := rand.Intn(9)
+				//// get 0-8 value
+				//tmpRand := rand.Intn(9)
+				// get 0-3 value
+				tmpRand := rand.Intn(4)
 				var rangeScanPlan plans.Plan
 				switch tmpRand {
 				case 0: // start only
@@ -1091,22 +1093,22 @@ func InnerTestParallelTxnsQueryingIndexUsedColumns[T int32 | float32 | string](t
 					rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, &rangeStartKey, &rangeEndKey, indexKind)
 				case 3: // not specified both
 					rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, nil, nil, indexKind)
-				case 4: // start only (not exisiting val)
-					tmpStartKey := samehada_util.StrideAdd(rangeStartKey, diffToMakeNoExist).(T)
-					rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, &tmpStartKey, nil, indexKind)
-				case 5: // end only (not existing val)
-					tmpEndKey := samehada_util.StrideAdd(rangeEndKey, diffToMakeNoExist).(T)
-					rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, nil, &tmpEndKey, indexKind)
-				case 6: // start and end (start val is not existing one)
-					tmpStartKey := samehada_util.StrideAdd(rangeStartKey, diffToMakeNoExist).(T)
-					rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, &tmpStartKey, &rangeEndKey, indexKind)
-				case 7: // start and end (start val is not existing one)
-					tmpEndKey := samehada_util.StrideAdd(rangeEndKey, diffToMakeNoExist).(T)
-					rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, &rangeStartKey, &tmpEndKey, indexKind)
-				case 8: // start and end (end val is not existing one)
-					tmpStartKey := samehada_util.StrideAdd(rangeStartKey, diffToMakeNoExist).(T)
-					tmpEndKey := samehada_util.StrideAdd(rangeEndKey, diffToMakeNoExist).(T)
-					rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, &tmpStartKey, &tmpEndKey, indexKind)
+					//case 4: // start only (not exisiting val)
+					//	tmpStartKey := samehada_util.StrideAdd(rangeStartKey, diffToMakeNoExist).(T)
+					//	rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, &tmpStartKey, nil, indexKind)
+					//case 5: // end only (not existing val)
+					//	tmpEndKey := samehada_util.StrideAdd(rangeEndKey, diffToMakeNoExist).(T)
+					//	rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, nil, &tmpEndKey, indexKind)
+					//case 6: // start and end (start val is not existing one)
+					//	tmpStartKey := samehada_util.StrideAdd(rangeStartKey, diffToMakeNoExist).(T)
+					//	rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, &tmpStartKey, &rangeEndKey, indexKind)
+					//case 7: // start and end (start val is not existing one)
+					//	tmpEndKey := samehada_util.StrideAdd(rangeEndKey, diffToMakeNoExist).(T)
+					//	rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, &rangeStartKey, &tmpEndKey, indexKind)
+					//case 8: // start and end (end val is not existing one)
+					//	tmpStartKey := samehada_util.StrideAdd(rangeStartKey, diffToMakeNoExist).(T)
+					//	tmpEndKey := samehada_util.StrideAdd(rangeEndKey, diffToMakeNoExist).(T)
+					//	rangeScanPlan = createSpecifiedRangeScanPlanNode[T](c, tableMetadata, keyType, 0, &tmpStartKey, &tmpEndKey, indexKind)
 				}
 
 				txn_ := txnMgr.Begin(nil)
diff --git a/lib/storage/index/btree_index.go b/lib/storage/index/btree_index.go
index 9f63ad42..3603746a 100644
--- a/lib/storage/index/btree_index.go
+++ b/lib/storage/index/btree_index.go
@@ -100,8 +100,8 @@ func (btidx *BTreeIndex) insertEntryInner(key *tuple.Tuple, rid page.RID, txn in
 	convedKeyVal := samehada_util.EncodeValueAndRIDToDicOrderComparableVarchar(&orgKeyVal, &rid)
 
 	if isNoLock == false {
-		btidx.rwMtx.Lock()
-		defer btidx.rwMtx.Unlock()
+		btidx.rwMtx.RLock()
+		defer btidx.rwMtx.RUnlock()
 	}
 
 	ridBytes := samehada_util.PackRIDto8bytes(&rid)
@@ -124,8 +124,8 @@ func (btidx *BTreeIndex) deleteEntryInner(key *tuple.Tuple, rid page.RID, txn in
 	convedKeyVal := samehada_util.EncodeValueAndRIDToDicOrderComparableVarchar(&orgKeyVal, &rid)
 
 	if isNoLock == false {
-		btidx.rwMtx.Lock()
-		defer btidx.rwMtx.Unlock()
+		btidx.rwMtx.RLock()
+		defer btidx.rwMtx.RUnlock()
 	}
 	btidx.container.DeleteKey(convedKeyVal.SerializeOnlyVal(), 0)
 }