diff --git a/src/query/src/qast.c b/src/query/src/qast.c
index 4524c5b2492d578aad36faae1b690f201ac9398d..6674dc1abafdae5b9ccd71df7395609a551ce6ef 100644
--- a/src/query/src/qast.c
+++ b/src/query/src/qast.c
@@ -926,7 +926,7 @@ void tSQLBinaryExprTrv(tExprNode *pExprs, int32_t *val, int16_t *ids) {
   }
 }
 
-static int32_t exprTreeToBinaryImpl(tExprNode* pExprTree, SBuffer* pBuf) {
+static void exprTreeToBinaryImpl(tExprNode* pExprTree, SBuffer* pBuf) {
   tbufWrite(pBuf, &pExprTree->nodeType, sizeof(pExprTree->nodeType));
   
   if (pExprTree->nodeType == TSQL_NODE_VALUE) {
@@ -973,7 +973,7 @@ SBuffer exprTreeToBinary(tExprNode* pExprTree) {
   return buf;
 }
 
-static tExprNode* exprTreeFromBinaryImpl(tExprNode** pExprTree, SBuffer* pBuf) {
+static void exprTreeFromBinaryImpl(tExprNode** pExprTree, SBuffer* pBuf) {
   tExprNode* pExpr = calloc(1, sizeof(tExprNode));
   tbufReadToBuffer(pBuf, &pExpr->nodeType, sizeof(pExpr->nodeType));
   
@@ -1014,7 +1014,7 @@ static tExprNode* exprTreeFromBinaryImpl(tExprNode** pExprTree, SBuffer* pBuf) {
 
 tExprNode* exprTreeFromBinary(const void* pBuf, size_t size) {
   SBuffer rbuf = {0};
-  int32_t code = tbufBeginRead(&rbuf, pBuf, size);
+  /*int32_t code =*/ tbufBeginRead(&rbuf, pBuf, size);
   
   tExprNode* pExprNode = NULL;
   exprTreeFromBinaryImpl(&pExprNode, &rbuf);
diff --git a/src/util/src/ihash.c b/src/util/src/ihash.c
index 6b58d8ef31c3b83c8c0160364abf2ae97132d0f0..e1c7cb0e5897b4492dfa101c359bd8265e70d9ef 100644
--- a/src/util/src/ihash.c
+++ b/src/util/src/ihash.c
@@ -221,10 +221,9 @@ void taosCleanUpIntHashWithFp(void *handle, void (*fp)(char *)) {
 void taosVisitIntHashWithFp(void *handle, int (*fp)(char *, void *), void *param) {
   IHashObj * pObj;
   IHashNode *pNode, *pNext;
-  char *     pData = NULL;
 
   pObj = (IHashObj *)handle;
-  if (pObj == NULL || pObj->maxSessions <= 0) return NULL;
+  if (pObj == NULL || pObj->maxSessions <= 0) return;
 
   pthread_mutex_lock(&pObj->mutex);
 
@@ -245,11 +244,10 @@ void taosVisitIntHashWithFp(void *handle, int (*fp)(char *, void *), void *param
 int32_t taosGetIntHashSize(void *handle) {
   IHashObj * pObj;
   IHashNode *pNode, *pNext;
-  char *     pData = NULL;
   int32_t    num = 0;
 
   pObj = (IHashObj *)handle;
-  if (pObj == NULL || pObj->maxSessions <= 0) return NULL;
+  if (pObj == NULL || pObj->maxSessions <= 0) return 0;
 
   pthread_mutex_lock(&pObj->mutex);
 
diff --git a/src/vnode/tsdb/src/tsdbRead.c b/src/vnode/tsdb/src/tsdbRead.c
index 599d8bd34738d047f2e3331d3a242f08976bf7b9..a62577016048b1faf0c99ba1c000ac75f11e79bd 100644
--- a/src/vnode/tsdb/src/tsdbRead.c
+++ b/src/vnode/tsdb/src/tsdbRead.c
@@ -444,6 +444,7 @@ static bool doLoadDataFromFileBlock(STsdbQueryHandle *pQueryHandle) {
   }
   
   tsdbLoadDataBlock(pFile, pBlock, 1, pCheckInfo->pDataCols, data);
+  return true;
 }
 
 static bool loadQualifiedDataFromFileBlock(STsdbQueryHandle *pQueryHandle) {
@@ -484,7 +485,7 @@ bool moveToNextBlock(STsdbQueryHandle *pQueryHandle, int32_t step) {
          (pQueryHandle->cur.slot == pCheckInfo->compIndex[tid].numOfSuperBlocks - 1)) ||
         (step == QUERY_DESC_FORWARD_STEP && (pQueryHandle->cur.slot == 0))) {
       // temporarily keep the position value, in case of no data qualified when move forwards(backwards)
-      SQueryFilePos save = pQueryHandle->cur;
+//      SQueryFilePos save = pQueryHandle->cur;
       SFileGroup*   fgroup = tsdbGetFileGroupNext(&pCheckInfo->fileIter);
 
       int32_t fid = -1;
@@ -524,6 +525,8 @@ bool moveToNextBlock(STsdbQueryHandle *pQueryHandle, int32_t step) {
   } else {  // data in cache
     return hasMoreDataInCacheForSingleModel(pQueryHandle);
   }
+  
+  return false;
 }
 
 int vnodeBinarySearchKey(char *pValue, int num, TSKEY key, int order) {
@@ -751,8 +754,6 @@ static bool getQualifiedDataBlock(STsdbQueryHandle *pQueryHandle, STableCheckInf
       break;
     }
   
-    SFile* pFile = &pCheckInfo->pFileGroup->files[TSDB_FILE_TYPE_DATA];
-  
     // no data block in current file, try next
     if (pCheckInfo->compIndex[tid].numOfSuperBlocks == 0) {
       dTrace("QInfo:%p no data block in file, fid:%d, tid:%d, try next", pQueryHandle->qinfo,
@@ -836,7 +837,7 @@ static bool hasMoreDataInFileForSingleTableModel(STsdbQueryHandle* pHandle) {
   assert(pHandle->activeIndex == 0 && taosArrayGetSize(pHandle->pTableCheckInfo) == 1);
   
   STsdbFileH* pFileHandle = tsdbGetFile(pHandle->pTsdb);
-  SQueryFilePos* cur = &pHandle->cur;
+//  SQueryFilePos* cur = &pHandle->cur;
   
   STableCheckInfo* pCheckInfo = taosArrayGet(pHandle->pTableCheckInfo, pHandle->activeIndex);
   
@@ -1329,20 +1330,19 @@ static int32_t doQueryTableList(STable* pSTable, SArray* pRes, const char* pCond
   return TSDB_CODE_SUCCESS;
 }
 
-// SArray *tsdbQueryTableList(struct STsdbRepo* tsdb, int64_t uid, const wchar_t *pTagCond, size_t len) {
 SArray *tsdbQueryTableList(tsdb_repo_t* tsdb, int64_t uid, const wchar_t *pTagCond, size_t len) {
   // no condition, all tables created according to the stable will involved in querying
+  SArray* result = taosArrayInit(8, POINTER_BYTES);
+  
   if (pTagCond == NULL || wcslen(pTagCond) == 0) {
     return createTableIdArrayList(tsdb, uid);
   } else {
     char* str = convertTagQueryStr(pTagCond, len);
-    SArray* result = taosArrayInit(8, POINTER_BYTES);
     
     STable* pSTable = tsdbGetTableByUid(tsdbGetMeta(tsdb), uid);
     assert(pSTable != NULL);
     
-    if (doQueryTableList(pSTable, result, str) == TSDB_CODE_SUCCESS) {
-      return result;
-    }
+    doQueryTableList(pSTable, result, str);
+    return result;
   }
 }