diff --git a/src/common/src/tname.c b/src/common/src/tname.c
index 6727fc1961d5427d89c2e02be506ef854b705da0..68aa1be6b2ed0d9d1a248e6fc6ee2e701071fb21 100644
--- a/src/common/src/tname.c
+++ b/src/common/src/tname.c
@@ -50,7 +50,7 @@ SSchema tGetUserSpecifiedColumnSchema(tVariant* pVal, SStrToken* exprStr, const
   } else {
     size_t tlen = MIN(sizeof(s.name), exprStr->n + 1);
     tstrncpy(s.name, exprStr->z, tlen);
-    stringProcess(s.name, strlen(s.name));
+    stringProcess(s.name, (int32_t)strlen(s.name));
   }
 
   return s;
diff --git a/src/query/src/qSqlParser.c b/src/query/src/qSqlParser.c
index eaec7b23ad9324974b66dacb86bf974e8acb2da9..f927287015bf56f09c99d992b18fd2d226cb15f5 100644
--- a/src/query/src/qSqlParser.c
+++ b/src/query/src/qSqlParser.c
@@ -96,7 +96,7 @@ SArray *tSqlExprListAppend(SArray *pList, tSqlExpr *pNode, SStrToken *pDistinct,
       strncpy(item.aliasName, pToken->z, pToken->n);
       item.aliasName[pToken->n] = 0;
 
-      stringProcess(item.aliasName, strlen(item.aliasName));
+      stringProcess(item.aliasName, (int32_t)strlen(item.aliasName));
     }
 
     taosArrayPush(pList, &item);
diff --git a/src/util/src/ttokenizer.c b/src/util/src/ttokenizer.c
index ef1e7890ebd38cc0fb2c18dbb8fe7e396ce1475a..8fca99291164a429867a090c98a61156daa40af2 100644
--- a/src/util/src/ttokenizer.c
+++ b/src/util/src/ttokenizer.c
@@ -448,13 +448,13 @@ uint32_t tGetToken(char* z, uint32_t* tokenId) {
     }
     case '`': {
       for (i = 1; z[i]; i++) {
-        if(isprint(z[i]) == 0){
-          break;
-        }
-        if (z[i] == '`' && z[i+1] == '`') {
-          i++;
-          continue;
-        }
+//        if(isprint(z[i]) == 0){
+//          break;
+//        }
+//        if (z[i] == '`' && z[i+1] == '`') {
+//          i++;
+//          continue;
+//        }
         if (z[i] == '`') {
           i++;
           *tokenId = TK_ID;
diff --git a/src/util/src/tutil.c b/src/util/src/tutil.c
index e5a326661e1b14cf443012f86f1111f6134015fa..ad359bd15f7e1808b4cd2ab99ac33f3d326dd9cd 100644
--- a/src/util/src/tutil.c
+++ b/src/util/src/tutil.c
@@ -78,6 +78,8 @@ int32_t strDealWithEscape(char *z, int32_t len){
 static int32_t strdequote(char *z, int32_t n){
   if(z == NULL || n < 2) return n;
   int32_t quote = z[0];
+  z[0] = 0;
+  z[n - 1] = 0;
   int32_t i = 1, j = 0;
   while (i < n) {
     if (i < n - 1 && z[i] == quote && z[i + 1] == quote) { // two consecutive quotation marks keep one