diff --git a/source/common/src/trow.c b/source/common/src/trow.c
index 9f4f053028..6391744851 100644
--- a/source/common/src/trow.c
+++ b/source/common/src/trow.c
@@ -24,7 +24,8 @@ const uint8_t tdVTypeByte[2][3] = {{
                                    },
                                    {
                                        // 1 bit
-                                       TD_VTYPE_NORM_BYTE_I, TD_VTYPE_NULL_BYTE_I,
+                                       TD_VTYPE_NORM_BYTE_I,  // normal
+                                       TD_VTYPE_NULL_BYTE_I,
                                        TD_VTYPE_NULL_BYTE_I,  // padding
                                    }
 
@@ -343,7 +344,7 @@ bool tdIsBitmapBlkNorm(const void *pBitmap, int32_t numOfBits, int8_t bitmapMode
     if (*((uint8_t *)pBitmap) != vTypeByte) {
       return false;
     }
-    pBitmap = POINTER_SHIFT(pBitmap, 1);
+    pBitmap = POINTER_SHIFT(pBitmap, i);
   }
 
   int32_t nLeft = numOfBits - nBytes * (bitmapMode == 0 ? TD_VTYPE_BITS : TD_VTYPE_BITS_I);
diff --git a/source/dnode/vnode/src/tsdb/tsdbReadImpl.c b/source/dnode/vnode/src/tsdb/tsdbReadImpl.c
index 8f2013e8e0..8f68883fde 100644
--- a/source/dnode/vnode/src/tsdb/tsdbReadImpl.c
+++ b/source/dnode/vnode/src/tsdb/tsdbReadImpl.c
@@ -246,6 +246,12 @@ int tsdbLoadBlockInfo(SReadH *pReadh, void *pTarget) {
   return 0;
 }
 
+static FORCE_INLINE void tsdbSwapDataCols(SDataCols *pDest, SDataCols *pSrc) {
+  SDataCol *pCols = pDest->cols;
+  memcpy(pDest, pSrc, sizeof(SDataCols));
+  pSrc->cols = pCols;
+}
+
 int tsdbLoadBlockData(SReadH *pReadh, SBlock *pBlock, SBlockInfo *pBlkInfo) {
   ASSERT(pBlock->numOfSubBlocks > 0);
   STsdbCfg *pCfg = REPO_CFG(pReadh->pRepo);
@@ -277,7 +283,7 @@ int tsdbLoadBlockData(SReadH *pReadh, SBlock *pBlock, SBlockInfo *pBlkInfo) {
                         TD_SUPPORT_UPDATE(update), TD_VER_MAX) < 0) {
       return -1;
     }
-    memcpy(pReadh->pDCols[0], pReadh->pDCols[1], sizeof(SDataCols));
+    tsdbSwapDataCols(pReadh->pDCols[0], pReadh->pDCols[1]);
     ASSERT(pReadh->pDCols[0]->bitmapMode != 0);
   }
 
@@ -319,10 +325,11 @@ int tsdbLoadBlockDataCols(SReadH *pReadh, SBlock *pBlock, SBlockInfo *pBlkInfo,
                         TD_SUPPORT_UPDATE(update), TD_VER_MAX) < 0) {
       return -1;
     }
-    memcpy(pReadh->pDCols[0], pReadh->pDCols[1], sizeof(SDataCols));
+    tsdbSwapDataCols(pReadh->pDCols[0], pReadh->pDCols[1]);
     ASSERT(pReadh->pDCols[0]->bitmapMode != 0);
   }
 
+
   if (mergeBitmap && !tdDataColsIsBitmapI(pReadh->pDCols[0])) {
     for (int i = 0; i < numOfColsIds; ++i) {
       SDataCol *pDataCol = pReadh->pDCols[0]->cols + i;