diff --git a/src/client/inc/tsclient.h b/src/client/inc/tsclient.h
index c03e3be4ed..24e0f48ec9 100644
--- a/src/client/inc/tsclient.h
+++ b/src/client/inc/tsclient.h
@@ -285,8 +285,8 @@ typedef struct STscObj {
   void *             pTimer;
   char               user[TSDB_USER_LEN];
   char               pass[TSDB_KEY_LEN];
-  char               acctId[TSDB_DB_NAME_LEN];
-  char               db[TSDB_TABLE_ID_LEN];
+  char               acctId[TSDB_ACCT_LEN];
+  char               db[TSDB_DB_NAME_LEN];
   char               sversion[TSDB_VERSION_LEN];
   char               writeAuth : 1;
   char               superAuth : 1;
diff --git a/src/client/src/tscLocal.c b/src/client/src/tscLocal.c
index 91e51f16ed..52240941f2 100644
--- a/src/client/src/tscLocal.c
+++ b/src/client/src/tscLocal.c
@@ -132,7 +132,7 @@ static int32_t tscSetValueToResObj(SSqlObj *pSql, int32_t rowLen) {
   for (int32_t i = 0; i < numOfRows; ++i) {
     TAOS_FIELD *pField = tscFieldInfoGetField(&pQueryInfo->fieldsInfo, 0);
     char* dst = pRes->data + tscFieldInfoGetOffset(pQueryInfo, 0) * totalNumOfRows + pField->bytes * i;
-    STR_WITH_MAXSIZE_TO_VARSTR(dst, pSchema[i].name, TSDB_COL_NAME_LEN);
+    STR_WITH_MAXSIZE_TO_VARSTR(dst, pSchema[i].name, TSDB_COL_NAME_LEN - 1);
 
     char *type = tDataTypeDesc[pSchema[i].type].aName;
 
@@ -171,7 +171,7 @@ static int32_t tscSetValueToResObj(SSqlObj *pSql, int32_t rowLen) {
     // field name
     TAOS_FIELD *pField = tscFieldInfoGetField(&pQueryInfo->fieldsInfo, 0);
     char* output = pRes->data + tscFieldInfoGetOffset(pQueryInfo, 0) * totalNumOfRows + pField->bytes * i;
-    STR_WITH_MAXSIZE_TO_VARSTR(output, pSchema[i].name, TSDB_COL_NAME_LEN);
+    STR_WITH_MAXSIZE_TO_VARSTR(output, pSchema[i].name, TSDB_COL_NAME_LEN - 1);
 
     // type name
     pField = tscFieldInfoGetField(&pQueryInfo->fieldsInfo, 1);
@@ -211,18 +211,18 @@ static int32_t tscBuildTableSchemaResultFields(SSqlObj *pSql, int32_t numOfCols,
   SQueryInfo* pQueryInfo = tscGetQueryInfoDetail(&pSql->cmd, 0);
   pQueryInfo->order.order = TSDB_ORDER_ASC;
 
-  TAOS_FIELD f = {.type = TSDB_DATA_TYPE_BINARY, .bytes = TSDB_COL_NAME_LEN + VARSTR_HEADER_SIZE};
-  strncpy(f.name, "Field", TSDB_COL_NAME_LEN);
+  TAOS_FIELD f = {.type = TSDB_DATA_TYPE_BINARY, .bytes = (TSDB_COL_NAME_LEN - 1) + VARSTR_HEADER_SIZE};
+  tstrncpy(f.name, "Field", sizeof(f.name));
   
   SFieldSupInfo* pInfo = tscFieldInfoAppend(&pQueryInfo->fieldsInfo, &f);
   pInfo->pSqlExpr = tscSqlExprAppend(pQueryInfo, TSDB_FUNC_TS_DUMMY, &index, TSDB_DATA_TYPE_BINARY,
-      TSDB_COL_NAME_LEN + VARSTR_HEADER_SIZE, TSDB_COL_NAME_LEN, false);
+      (TSDB_COL_NAME_LEN - 1) + VARSTR_HEADER_SIZE, (TSDB_COL_NAME_LEN - 1), false);
   
-  rowLen += (TSDB_COL_NAME_LEN + VARSTR_HEADER_SIZE);
+  rowLen += ((TSDB_COL_NAME_LEN - 1) + VARSTR_HEADER_SIZE);
 
   f.bytes = typeColLength;
   f.type = TSDB_DATA_TYPE_BINARY;
-  strncpy(f.name, "Type", TSDB_COL_NAME_LEN);
+  tstrncpy(f.name, "Type", sizeof(f.name));
   
   pInfo = tscFieldInfoAppend(&pQueryInfo->fieldsInfo, &f);
   pInfo->pSqlExpr = tscSqlExprAppend(pQueryInfo, TSDB_FUNC_TS_DUMMY, &index, TSDB_DATA_TYPE_BINARY, typeColLength,
@@ -232,7 +232,7 @@ static int32_t tscBuildTableSchemaResultFields(SSqlObj *pSql, int32_t numOfCols,
 
   f.bytes = sizeof(int32_t);
   f.type = TSDB_DATA_TYPE_INT;
-  strncpy(f.name, "Length", TSDB_COL_NAME_LEN);
+  tstrncpy(f.name, "Length", sizeof(f.name));
   
   pInfo = tscFieldInfoAppend(&pQueryInfo->fieldsInfo, &f);
   pInfo->pSqlExpr = tscSqlExprAppend(pQueryInfo, TSDB_FUNC_TS_DUMMY, &index, TSDB_DATA_TYPE_INT, sizeof(int32_t),
@@ -242,7 +242,7 @@ static int32_t tscBuildTableSchemaResultFields(SSqlObj *pSql, int32_t numOfCols,
 
   f.bytes = noteColLength;
   f.type = TSDB_DATA_TYPE_BINARY;
-  strncpy(f.name, "Note", TSDB_COL_NAME_LEN);
+  tstrncpy(f.name, "Note", sizeof(f.name));
   
   pInfo = tscFieldInfoAppend(&pQueryInfo->fieldsInfo, &f);
   pInfo->pSqlExpr = tscSqlExprAppend(pQueryInfo, TSDB_FUNC_TS_DUMMY, &index, TSDB_DATA_TYPE_BINARY, noteColLength,
@@ -286,7 +286,7 @@ static void tscProcessCurrentUser(SSqlObj *pSql) {
 }
 
 static void tscProcessCurrentDB(SSqlObj *pSql) {
-  char db[TSDB_DB_NAME_LEN + 1] = {0};
+  char db[TSDB_DB_NAME_LEN] = {0};
   extractDBName(pSql->pTscObj->db, db);
   
   SQueryInfo* pQueryInfo = tscGetQueryInfoDetail(&pSql->cmd, 0);
diff --git a/src/client/src/tscParseInsert.c b/src/client/src/tscParseInsert.c
index cbc83c6e75..c4749e4611 100644
--- a/src/client/src/tscParseInsert.c
+++ b/src/client/src/tscParseInsert.c
@@ -795,7 +795,7 @@ static int32_t tscCheckIfCreateTable(char **sqlstr, SSqlObj *pSql) {
     STableMetaInfo *pSTableMeterMetaInfo = tscGetMetaInfo(pQueryInfo, STABLE_INDEX);
     tscSetTableFullName(pSTableMeterMetaInfo, &sToken, pSql);
 
-    strncpy(pTag->name, pSTableMeterMetaInfo->name, TSDB_TABLE_ID_LEN);
+    tstrncpy(pTag->name, pSTableMeterMetaInfo->name, sizeof(pTag->name));
     code = tscGetTableMeta(pSql, pSTableMeterMetaInfo);
     if (code != TSDB_CODE_SUCCESS) {
       return code;
@@ -989,7 +989,7 @@ static int32_t tscCheckIfCreateTable(char **sqlstr, SSqlObj *pSql) {
 
 int validateTableName(char *tblName, int len) {
   char buf[TSDB_TABLE_ID_LEN] = {0};
-  strncpy(buf, tblName, len);
+  tstrncpy(buf, tblName, sizeof(buf));
 
   SSQLToken token = {.n = len, .type = TK_ID, .z = buf};
   tSQLGetToken(buf, &token.type);
@@ -1512,7 +1512,7 @@ void tscProcessMultiVnodesInsertFromFile(SSqlObj *pSql) {
     }
     pCmd->count = 1;
 
-    strncpy(path, pDataBlock->filename, PATH_MAX);
+    tstrncpy(path, pDataBlock->filename, sizeof(path));
 
     FILE *fp = fopen(path, "r");
     if (fp == NULL) {
@@ -1520,7 +1520,7 @@ void tscProcessMultiVnodesInsertFromFile(SSqlObj *pSql) {
       continue;
     }
 
-    strncpy(pTableMetaInfo->name, pDataBlock->tableId, TSDB_TABLE_ID_LEN);
+    tstrncpy(pTableMetaInfo->name, pDataBlock->tableId, sizeof(pTableMetaInfo->name));
     memset(pDataBlock->pData, 0, pDataBlock->nAllocSize);
 
     int32_t ret = tscGetTableMeta(pSql, pTableMetaInfo);
diff --git a/src/client/src/tscProfile.c b/src/client/src/tscProfile.c
index 79d00bf5dc..55243c4382 100644
--- a/src/client/src/tscProfile.c
+++ b/src/client/src/tscProfile.c
@@ -239,8 +239,7 @@ int tscBuildQueryStreamDesc(void *pMsg, STscObj *pObj) {
       continue;
     }
 
-    strncpy(pQdesc->sql, pSql->sqlstr, TSDB_SHOW_SQL_LEN - 1);
-    pQdesc->sql[TSDB_SHOW_SQL_LEN - 1] = 0;
+    tstrncpy(pQdesc->sql, pSql->sqlstr, sizeof(pQdesc->sql));
     pQdesc->stime = htobe64(pSql->stime);
     pQdesc->queryId = htonl(pSql->queryId);
     pQdesc->useconds = htobe64(pSql->res.useconds);
@@ -256,8 +255,7 @@ int tscBuildQueryStreamDesc(void *pMsg, STscObj *pObj) {
 
   SSqlStream *pStream = pObj->streamList;
   while (pStream) {
-    strncpy(pSdesc->sql, pStream->pSql->sqlstr, TSDB_SHOW_SQL_LEN - 1);
-    pSdesc->sql[TSDB_SHOW_SQL_LEN - 1] = 0;
+    tstrncpy(pSdesc->sql, pStream->pSql->sqlstr, sizeof(pSdesc->sql));
     pSdesc->streamId = htonl(pStream->streamId);
     pSdesc->num = htobe64(pStream->num);
 
diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index f29c886cba..ab2d7d7830 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -348,7 +348,7 @@ int32_t tscToSQLCmd(SSqlObj* pSql, struct SSqlInfo* pInfo) {
         return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg1);
       }
 
-      if (pToken->n > TSDB_TABLE_NAME_LEN) {
+      if (pToken->n >= TSDB_TABLE_NAME_LEN) {
         return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg2);
       }
 
@@ -933,7 +933,7 @@ bool validateOneTags(SSqlCmd* pCmd, TAOS_FIELD* pTagField) {
   SSchema* pSchema = tscGetTableSchema(pTableMeta);
 
   for (int32_t i = 0; i < numOfTags + numOfCols; ++i) {
-    if (strncasecmp(pTagField->name, pSchema[i].name, TSDB_COL_NAME_LEN) == 0) {
+    if (strncasecmp(pTagField->name, pSchema[i].name, sizeof(pTagField->name) - 1) == 0) {
       invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg2);
       return false;
     }
@@ -993,7 +993,7 @@ bool validateOneColumn(SSqlCmd* pCmd, TAOS_FIELD* pColField) {
 
   // field name must be unique
   for (int32_t i = 0; i < numOfTags + numOfCols; ++i) {
-    if (strncasecmp(pColField->name, pSchema[i].name, TSDB_COL_NAME_LEN) == 0) {
+    if (strncasecmp(pColField->name, pSchema[i].name, sizeof(pColField->name) - 1) == 0) {
       invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg2);
       return false;
     }
@@ -1005,7 +1005,8 @@ bool validateOneColumn(SSqlCmd* pCmd, TAOS_FIELD* pColField) {
 /* is contained in pFieldList or not */
 static bool has(tFieldList* pFieldList, int32_t startIdx, const char* name) {
   for (int32_t j = startIdx; j < pFieldList->nField; ++j) {
-    if (strncasecmp(name, pFieldList->p[j].name, TSDB_COL_NAME_LEN) == 0) return true;
+    TAOS_FIELD* field = pFieldList->p + j;
+    if (strncasecmp(name, field->name, sizeof(field->name) - 1) == 0) return true;
   }
 
   return false;
@@ -1041,7 +1042,7 @@ int32_t setObjFullName(char* fullName, const char* account, SSQLToken* pDB, SSQL
 
   /* db name is not specified, the tableName dose not include db name */
   if (pDB != NULL) {
-    if (pDB->n > TSDB_DB_NAME_LEN) {
+    if (pDB->n >= TSDB_DB_NAME_LEN) {
       return TSDB_CODE_TSC_INVALID_SQL;
     }
 
@@ -1060,7 +1061,7 @@ int32_t setObjFullName(char* fullName, const char* account, SSQLToken* pDB, SSQL
       }
     } else {  // pDB == NULL, the db prefix name is specified in tableName
       /* the length limitation includes tablename + dbname + sep */
-      if (tableName->n > TSDB_TABLE_NAME_LEN + TSDB_DB_NAME_LEN + tListLen(TS_PATH_DELIMITER)) {
+      if (tableName->n > (TSDB_TABLE_NAME_LEN - 1) + (TSDB_DB_NAME_LEN - 1) + sizeof(TS_PATH_DELIMITER)) {
         return TSDB_CODE_TSC_INVALID_SQL;
       }
     }
@@ -1166,7 +1167,7 @@ int32_t parseSelectClause(SSqlCmd* pCmd, int32_t clauseIndex, tSQLExprList* pSel
         
         /* todo alias name should use the original sql string */
         char* name = (pItem->aliasName != NULL)? pItem->aliasName:arithmeticExprStr;
-        strncpy(pExpr->aliasName, name, TSDB_COL_NAME_LEN);
+        tstrncpy(pExpr->aliasName, name, sizeof(pExpr->aliasName));
         
         tExprNode* pNode = NULL;
         SArray* colList = taosArrayInit(10, sizeof(SColIndex));
@@ -1308,7 +1309,7 @@ static void addProjectQueryCol(SQueryInfo* pQueryInfo, int32_t startPos, SColumn
   SSchema* pSchema = tscGetTableColumnSchema(pTableMeta, pIndex->columnIndex);
 
   char* colName = (pItem->aliasName == NULL) ? pSchema->name : pItem->aliasName;
-  strncpy(pExpr->aliasName, colName, tListLen(pExpr->aliasName));
+  tstrncpy(pExpr->aliasName, colName, sizeof(pExpr->aliasName));
   
   SColumnList ids = {0};
   ids.num = 1;
@@ -1358,7 +1359,7 @@ static int32_t doAddProjectionExprAndResultFields(SQueryInfo* pQueryInfo, SColum
 
   for (int32_t j = 0; j < numOfTotalColumns; ++j) {
     SSqlExpr* pExpr = doAddProjectCol(pQueryInfo, startPos + j, j, pIndex->tableIndex);
-    strncpy(pExpr->aliasName, pSchema[j].name, tListLen(pExpr->aliasName));
+    tstrncpy(pExpr->aliasName, pSchema[j].name, sizeof(pExpr->aliasName));
 
     pIndex->columnIndex = j;
     SColumnList ids = {0};
@@ -1401,7 +1402,7 @@ int32_t addProjectionExprAndResultField(SQueryInfo* pQueryInfo, tSQLExprItem* pI
     }
 
     if (index.columnIndex == TSDB_TBNAME_COLUMN_INDEX) {
-      SSchema colSchema = {.type = TSDB_DATA_TYPE_BINARY, .bytes = TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE};
+      SSchema colSchema = {.type = TSDB_DATA_TYPE_BINARY, .bytes = (TSDB_TABLE_NAME_LEN - 1) + VARSTR_HEADER_SIZE};
       strcpy(colSchema.name, TSQL_TBNAME_L);
 
       tscAddSpecialColumnForSelect(pQueryInfo, startPos, TSDB_FUNC_TAGPRJ, &index, &colSchema, true);
@@ -1448,11 +1449,11 @@ static int32_t setExprInfoForFunctions(SQueryInfo* pQueryInfo, SSchema* pSchema,
   if (aliasName != NULL) {
     strcpy(columnName, aliasName);
   } else {
-    getRevisedName(columnName, functionID, TSDB_COL_NAME_LEN, pSchema[pColIndex->columnIndex].name);
+    getRevisedName(columnName, functionID, sizeof(columnName) - 1, pSchema[pColIndex->columnIndex].name);
   }
   
   SSqlExpr* pExpr = tscSqlExprAppend(pQueryInfo, functionID, pColIndex, type, bytes, bytes, false);
-  strncpy(pExpr->aliasName, columnName, tListLen(pExpr->aliasName));
+  tstrncpy(pExpr->aliasName, columnName, sizeof(pExpr->aliasName));
   
   // for all queries, the timestamp column needs to be loaded
   SColumnIndex index = {.tableIndex = pColIndex->tableIndex, .columnIndex = PRIMARYKEY_TIMESTAMP_COL_INDEX};
@@ -1536,7 +1537,7 @@ int32_t addExprAndResultField(SQueryInfo* pQueryInfo, int32_t colIndex, tSQLExpr
       }
       
       memset(pExpr->aliasName, 0, tListLen(pExpr->aliasName));
-      getColumnName(pItem, pExpr->aliasName, TSDB_COL_NAME_LEN);
+      getColumnName(pItem, pExpr->aliasName, sizeof(pExpr->aliasName) - 1);
       
       SColumnList ids = getColumnList(1, index.tableIndex, index.columnIndex);
       if (finalResult) {
@@ -1651,7 +1652,7 @@ int32_t addExprAndResultField(SQueryInfo* pQueryInfo, int32_t colIndex, tSQLExpr
       ids.ids[0] = index;
   
       memset(pExpr->aliasName, 0, tListLen(pExpr->aliasName));
-      getColumnName(pItem, pExpr->aliasName, TSDB_COL_NAME_LEN);
+      getColumnName(pItem, pExpr->aliasName, sizeof(pExpr->aliasName) - 1);
   
       if (finalResult) {
         int32_t numOfOutput = tscNumOfFields(pQueryInfo);
@@ -1851,7 +1852,7 @@ int32_t addExprAndResultField(SQueryInfo* pQueryInfo, int32_t colIndex, tSQLExpr
       }
   
       memset(pExpr->aliasName, 0, tListLen(pExpr->aliasName));
-      getColumnName(pItem, pExpr->aliasName, TSDB_COL_NAME_LEN);
+      getColumnName(pItem, pExpr->aliasName, sizeof(pExpr->aliasName) - 1);
   
       SColumnList ids = getColumnList(1, 0, index.columnIndex);
       if (finalResult) {
@@ -2202,7 +2203,7 @@ int32_t setShowInfo(SSqlObj* pSql, struct SSqlInfo* pInfo) {
     if (pDbPrefixToken->type != 0) {
       assert(pDbPrefixToken->n >= 0);
 
-      if (pDbPrefixToken->n > TSDB_DB_NAME_LEN) {  // db name is too long
+      if (pDbPrefixToken->n >= TSDB_DB_NAME_LEN) {  // db name is too long
         return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg3);
       }
 
@@ -2229,7 +2230,7 @@ int32_t setShowInfo(SSqlObj* pSql, struct SSqlInfo* pInfo) {
         return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg6);
       }
 
-      if (pCmd->payloadLen > TSDB_TABLE_NAME_LEN) {
+      if (pCmd->payloadLen >= TSDB_TABLE_NAME_LEN) {
         return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg2);
       }
     }
@@ -3997,7 +3998,7 @@ int32_t tsRewriteFieldNameIfNecessary(SQueryInfo* pQueryInfo) {
 
   for (int32_t i = 0; i < pQueryInfo->fieldsInfo.numOfOutput; ++i) {
     char* fieldName = tscFieldInfoGetField(&pQueryInfo->fieldsInfo, i)->name;
-    for (int32_t j = 0; j < TSDB_COL_NAME_LEN && fieldName[j] != 0; ++j) {
+    for (int32_t j = 0; j < (TSDB_COL_NAME_LEN - 1) && fieldName[j] != 0; ++j) {
       for (int32_t k = 0; k < tListLen(rep); ++k) {
         if (fieldName[j] == rep[k]) {
           fieldName[j] = '_';
@@ -4013,7 +4014,7 @@ int32_t tsRewriteFieldNameIfNecessary(SQueryInfo* pQueryInfo) {
   for (int32_t i = 0; i < pQueryInfo->fieldsInfo.numOfOutput; ++i) {
     char* fieldName = tscFieldInfoGetField(&pQueryInfo->fieldsInfo, i)->name;
     for (int32_t j = i + 1; j < pQueryInfo->fieldsInfo.numOfOutput; ++j) {
-      if (strncasecmp(fieldName, tscFieldInfoGetField(&pQueryInfo->fieldsInfo, j)->name, TSDB_COL_NAME_LEN) == 0) {
+      if (strncasecmp(fieldName, tscFieldInfoGetField(&pQueryInfo->fieldsInfo, j)->name, (TSDB_COL_NAME_LEN - 1)) == 0) {
         const char* msg = "duplicated column name in new table";
         return invalidSqlErrMsg(pQueryInfo->msg, msg);
       }
@@ -4368,7 +4369,7 @@ int32_t setAlterTableInfo(SSqlObj* pSql, struct SSqlInfo* pInfo) {
     }
 
     tVariantListItem* pItem = &pAlterSQL->varList->a[0];
-    if (pItem->pVar.nLen > TSDB_COL_NAME_LEN) {
+    if (pItem->pVar.nLen >= TSDB_COL_NAME_LEN) {
       return invalidSqlErrMsg(pQueryInfo->msg, msg9);
     }
 
@@ -4420,7 +4421,7 @@ int32_t setAlterTableInfo(SSqlObj* pSql, struct SSqlInfo* pInfo) {
       return TSDB_CODE_TSC_INVALID_SQL;
     }
 
-    char name[TSDB_COL_NAME_LEN + 1] = {0};
+    char name[TSDB_COL_NAME_LEN] = {0};
     strncpy(name, pVarList->a[0].pVar.pz, pVarList->a[0].pVar.nLen);
     TAOS_FIELD f = tscCreateField(TSDB_DATA_TYPE_INT, name, tDataTypeDesc[TSDB_DATA_TYPE_INT].nSize);
     tscFieldInfoAppend(&pQueryInfo->fieldsInfo, &f);
@@ -4522,8 +4523,8 @@ int32_t setAlterTableInfo(SSqlObj* pSql, struct SSqlInfo* pInfo) {
       return invalidSqlErrMsg(pQueryInfo->msg, msg18);
     }
 
-    char name1[TSDB_COL_NAME_LEN + 1] = {0};
-    strncpy(name1, pItem->pVar.pz, pItem->pVar.nLen);
+    char name1[TSDB_COL_NAME_LEN] = {0};
+    tstrncpy(name1, pItem->pVar.pz, sizeof(name1));
     TAOS_FIELD f = tscCreateField(TSDB_DATA_TYPE_INT, name1, tDataTypeDesc[TSDB_DATA_TYPE_INT].nSize);
     tscFieldInfoAppend(&pQueryInfo->fieldsInfo, &f);
   }
@@ -5232,7 +5233,7 @@ static int32_t doAddGroupbyColumnsOnDemand(SQueryInfo* pQueryInfo) {
     int16_t colIndex = pColIndex->colIndex;
     if (colIndex == TSDB_TBNAME_COLUMN_INDEX) {
       type = TSDB_DATA_TYPE_BINARY;
-      bytes = TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE; // todo extract method
+      bytes = (TSDB_TABLE_NAME_LEN - 1) + VARSTR_HEADER_SIZE; // todo extract method
       name = TSQL_TBNAME_L;
     } else {
       if (TSDB_COL_IS_TAG(pColIndex->flag)) {
@@ -5254,8 +5255,8 @@ static int32_t doAddGroupbyColumnsOnDemand(SQueryInfo* pQueryInfo) {
       SColumnIndex index = {.tableIndex = pQueryInfo->groupbyExpr.tableIndex, .columnIndex = colIndex};
       SSqlExpr* pExpr = tscSqlExprAppend(pQueryInfo, TSDB_FUNC_TAG, &index, type, bytes, bytes, true);
       
-      memset(pExpr->aliasName, 0, tListLen(pExpr->aliasName));
-      strncpy(pExpr->aliasName, name, TSDB_COL_NAME_LEN);
+      memset(pExpr->aliasName, 0, sizeof(pExpr->aliasName));
+      tstrncpy(pExpr->aliasName, name, sizeof(pExpr->aliasName));
       
       pExpr->colInfo.flag = TSDB_COL_TAG;
 
@@ -6019,7 +6020,7 @@ int32_t exprTreeFromSqlExpr(tExprNode **pExpr, const tSQLExpr* pSqlExpr, SArray*
   
       if (pCols != NULL) {  // record the involved columns
         SColIndex colIndex = {0};
-        strncpy(colIndex.name, pSchema->name, TSDB_COL_NAME_LEN);
+        tstrncpy(colIndex.name, pSchema->name, sizeof(colIndex.name));
         colIndex.colId = pSchema->colId;
         colIndex.colIndex = index.columnIndex;
         
diff --git a/src/client/src/tscSchemaUtil.c b/src/client/src/tscSchemaUtil.c
index 59415f842e..88417addf6 100644
--- a/src/client/src/tscSchemaUtil.c
+++ b/src/client/src/tscSchemaUtil.c
@@ -115,7 +115,7 @@ bool isValidSchema(struct SSchema* pSchema, int32_t numOfCols) {
 
     // 3. valid column names
     for (int32_t j = i + 1; j < numOfCols; ++j) {
-      if (strncasecmp(pSchema[i].name, pSchema[j].name, TSDB_COL_NAME_LEN) == 0) {
+      if (strncasecmp(pSchema[i].name, pSchema[j].name, sizeof(pSchema[i].name) - 1) == 0) {
         return false;
       }
     }
diff --git a/src/client/src/tscServer.c b/src/client/src/tscServer.c
index f96b979105..8815e463ad 100644
--- a/src/client/src/tscServer.c
+++ b/src/client/src/tscServer.c
@@ -866,7 +866,7 @@ int32_t tscBuildCreateDbMsg(SSqlObj *pSql, SSqlInfo *pInfo) {
 
   assert(pCmd->numOfClause == 1);
   STableMetaInfo *pTableMetaInfo = tscGetTableMetaInfoFromCmd(pCmd, pCmd->clauseIndex, 0);
-  strncpy(pCreateDbMsg->db, pTableMetaInfo->name, tListLen(pCreateDbMsg->db));
+  tstrncpy(pCreateDbMsg->db, pTableMetaInfo->name, sizeof(pCreateDbMsg->db));
 
   return TSDB_CODE_SUCCESS;
 }
@@ -1430,9 +1430,9 @@ int tscBuildConnectMsg(SSqlObj *pSql, SSqlInfo *pInfo) {
   char *db;  // ugly code to move the space
   db = strstr(pObj->db, TS_PATH_DELIMITER);
   db = (db == NULL) ? pObj->db : db + 1;
-  strcpy(pConnect->db, db);
-  strcpy(pConnect->clientVersion, version);
-  strcpy(pConnect->msgVersion, "");
+  tstrncpy(pConnect->db, db, sizeof(pConnect->db));
+  tstrncpy(pConnect->clientVersion, version, sizeof(pConnect->clientVersion));
+  tstrncpy(pConnect->msgVersion, "", sizeof(pConnect->msgVersion));
 
   return TSDB_CODE_SUCCESS;
 }
@@ -2153,8 +2153,8 @@ int tscProcessConnectRsp(SSqlObj *pSql) {
   strcpy(pObj->acctId, pConnect->acctId);  // copy acctId from response
   int32_t len = sprintf(temp, "%s%s%s", pObj->acctId, TS_PATH_DELIMITER, pObj->db);
 
-  assert(len <= tListLen(pObj->db));
-  strncpy(pObj->db, temp, tListLen(pObj->db));
+  assert(len <= sizeof(pObj->db));
+  tstrncpy(pObj->db, temp, sizeof(pObj->db));
   
   if (pConnect->ipList.numOfIps > 0) 
     tscSetMgmtIpList(&pConnect->ipList);
@@ -2338,7 +2338,7 @@ static int32_t getTableMetaFromMgmt(SSqlObj *pSql, STableMetaInfo *pTableMetaInf
   STableMetaInfo *pNewMeterMetaInfo = tscAddEmptyMetaInfo(pNewQueryInfo);
   assert(pNew->cmd.numOfClause == 1 && pNewQueryInfo->numOfTables == 1);
 
-  strncpy(pNewMeterMetaInfo->name, pTableMetaInfo->name, tListLen(pNewMeterMetaInfo->name));
+  tstrncpy(pNewMeterMetaInfo->name, pTableMetaInfo->name, sizeof(pNewMeterMetaInfo->name));
   memcpy(pNew->cmd.payload, pSql->cmd.payload, pSql->cmd.payloadLen);  // tag information if table does not exists.
   pNew->cmd.payloadLen = pSql->cmd.payloadLen;
   tscTrace("%p new pSqlObj:%p to get tableMeta, auto create:%d", pSql, pNew, pNew->cmd.autoCreated);
diff --git a/src/client/src/tscSql.c b/src/client/src/tscSql.c
index aab931cf93..5f2a8598db 100644
--- a/src/client/src/tscSql.c
+++ b/src/client/src/tscSql.c
@@ -86,21 +86,21 @@ SSqlObj *taosConnectImpl(const char *ip, const char *user, const char *pass, con
 
   pObj->signature = pObj;
 
-  strncpy(pObj->user, user, TSDB_USER_LEN);
+  tstrncpy(pObj->user, user, sizeof(pObj->user));
   taosEncryptPass((uint8_t *)pass, strlen(pass), pObj->pass);
 
   if (db) {
     int32_t len = strlen(db);
     /* db name is too long */
-    if (len > TSDB_DB_NAME_LEN) {
+    if (len >= TSDB_DB_NAME_LEN) {
       terrno = TSDB_CODE_TSC_INVALID_DB_LENGTH;
       rpcClose(pDnodeConn);
       free(pObj);
       return NULL;
     }
 
-    char tmp[TSDB_DB_NAME_LEN + 1] = {0};
-    strcpy(tmp, db);
+    char tmp[TSDB_DB_NAME_LEN] = {0};
+    tstrncpy(tmp, db, sizeof(tmp));
 
     strdequote(tmp);
     strtolower(pObj->db, tmp);
diff --git a/src/client/src/tscSubquery.c b/src/client/src/tscSubquery.c
index 84daf63b42..ddc41e52e5 100644
--- a/src/client/src/tscSubquery.c
+++ b/src/client/src/tscSubquery.c
@@ -1921,7 +1921,7 @@ static char *getArithemicInputSrc(void *param, const char *name, int32_t colId)
   
   for (int32_t i = 0; i < pSupport->numOfCols; ++i) {
     pExpr = taosArrayGetP(pSupport->exprList, i);
-    if (strncmp(name, pExpr->aliasName, TSDB_COL_NAME_LEN) == 0) {
+    if (strncmp(name, pExpr->aliasName, sizeof(pExpr->aliasName) - 1) == 0) {
       index = i;
       break;
     }
diff --git a/src/client/src/tscSystem.c b/src/client/src/tscSystem.c
index fd7d31aa9f..66fbf9fc97 100644
--- a/src/client/src/tscSystem.c
+++ b/src/client/src/tscSystem.c
@@ -180,7 +180,7 @@ static int taos_options_imp(TSDB_OPTION option, const char *pStr) {
       assert(cfg != NULL);
     
       if (cfg->cfgStatus <= TAOS_CFG_CSTATUS_OPTION) {
-        strncpy(configDir, pStr, TSDB_FILENAME_LEN);
+        tstrncpy(configDir, pStr, TSDB_FILENAME_LEN);
         cfg->cfgStatus = TAOS_CFG_CSTATUS_OPTION;
         tscPrint("set config file directory:%s", pStr);
       } else {
@@ -234,7 +234,7 @@ static int taos_options_imp(TSDB_OPTION option, const char *pStr) {
           tscPrint("failed to set locale:%s, current locale:%s", pStr, tsLocale);
         }
 
-        strncpy(tsLocale, locale, tListLen(tsLocale));
+        tstrncpy(tsLocale, locale, sizeof(tsLocale));
 
         char *charset = strrchr(tsLocale, sep);
         if (charset != NULL) {
@@ -249,7 +249,7 @@ static int taos_options_imp(TSDB_OPTION option, const char *pStr) {
               tscPrint("charset changed from %s to %s", tsCharset, charset);
             }
 
-            strncpy(tsCharset, charset, tListLen(tsCharset));
+            tstrncpy(tsCharset, charset, sizeof(tsCharset));
             cfg->cfgStatus = TAOS_CFG_CSTATUS_OPTION;
 
           } else {
@@ -286,7 +286,7 @@ static int taos_options_imp(TSDB_OPTION option, const char *pStr) {
             tscPrint("charset changed from %s to %s", tsCharset, pStr);
           }
 
-          strncpy(tsCharset, pStr, tListLen(tsCharset));
+          tstrncpy(tsCharset, pStr, sizeof(tsCharset));
           cfg->cfgStatus = TAOS_CFG_CSTATUS_OPTION;
         } else {
           tscPrint("charset:%s not valid", pStr);
@@ -324,7 +324,7 @@ static int taos_options_imp(TSDB_OPTION option, const char *pStr) {
 //          return -1;
 //        }
 
-        strncpy(tsSocketType, pStr, tListLen(tsSocketType));
+        tstrncpy(tsSocketType, pStr, sizeof(tsSocketType));
         cfg->cfgStatus = TAOS_CFG_CSTATUS_OPTION;
         tscPrint("socket type is set:%s", tsSocketType);
       }
diff --git a/src/client/src/tscUtil.c b/src/client/src/tscUtil.c
index caf424080d..a810e5d4be 100644
--- a/src/client/src/tscUtil.c
+++ b/src/client/src/tscUtil.c
@@ -801,7 +801,7 @@ int tscAllocPayload(SSqlCmd* pCmd, int size) {
 
 TAOS_FIELD tscCreateField(int8_t type, const char* name, int16_t bytes) {
   TAOS_FIELD f = { .type = type, .bytes = bytes, };
-  strncpy(f.name, name, TSDB_COL_NAME_LEN);
+  tstrncpy(f.name, name, sizeof(f.name));
   return f;
 }
 
@@ -966,12 +966,12 @@ static SSqlExpr* doBuildSqlExpr(SQueryInfo* pQueryInfo, int16_t functionId, SCol
     if (isTagCol) {
       SSchema* pSchema = tscGetTableTagSchema(pTableMetaInfo->pTableMeta);
       pExpr->colInfo.colId = pSchema[pColIndex->columnIndex].colId;
-      strncpy(pExpr->colInfo.name, pSchema[pColIndex->columnIndex].name, TSDB_COL_NAME_LEN);
+      tstrncpy(pExpr->colInfo.name, pSchema[pColIndex->columnIndex].name, sizeof(pExpr->colInfo.name));
     } else if (pTableMetaInfo->pTableMeta != NULL) {
       // in handling select database/version/server_status(), the pTableMeta is NULL
       SSchema* pSchema = tscGetTableColumnSchema(pTableMetaInfo->pTableMeta, pColIndex->columnIndex);
       pExpr->colInfo.colId = pSchema->colId;
-      strncpy(pExpr->colInfo.name, pSchema->name, TSDB_COL_NAME_LEN);
+      tstrncpy(pExpr->colInfo.name, pSchema->name, sizeof(pExpr->colInfo.name));
     }
   }
   
diff --git a/src/common/src/tglobal.c b/src/common/src/tglobal.c
index e010f7fe56..12754b164b 100644
--- a/src/common/src/tglobal.c
+++ b/src/common/src/tglobal.c
@@ -708,7 +708,7 @@ static void doInitGlobalConfig() {
   cfg.cfgType = TSDB_CFG_CTYPE_B_CONFIG | TSDB_CFG_CTYPE_B_CLIENT;
   cfg.minValue = 0;
   cfg.maxValue = 0;
-  cfg.ptrLength = TSDB_DB_NAME_LEN;
+  cfg.ptrLength = TSDB_DB_NAME_LEN - 1;
   cfg.unitType = TAOS_CFG_UTYPE_NONE;
   taosInitConfigOption(cfg);
 
@@ -923,7 +923,7 @@ static void doInitGlobalConfig() {
   cfg.cfgType = TSDB_CFG_CTYPE_B_CONFIG | TSDB_CFG_CTYPE_B_SHOW;
   cfg.minValue = 0;
   cfg.maxValue = 0;
-  cfg.ptrLength = TSDB_DB_NAME_LEN;
+  cfg.ptrLength = TSDB_DB_NAME_LEN - 1;
   cfg.unitType = TAOS_CFG_UTYPE_NONE;
   taosInitConfigOption(cfg);
 
diff --git a/src/common/src/tname.c b/src/common/src/tname.c
index 3566f26abd..d2f5dfc4f7 100644
--- a/src/common/src/tname.c
+++ b/src/common/src/tname.c
@@ -28,8 +28,7 @@ void extractTableName(const char* tableId, char* name) {
   size_t s1 = strcspn(tableId, &TS_PATH_DELIMITER[0]);
   size_t s2 = strcspn(&tableId[s1 + 1], &TS_PATH_DELIMITER[0]);
   
-  strncpy(name, &tableId[s1 + s2 + 2], TSDB_TABLE_NAME_LEN);
-  name[TSDB_TABLE_NAME_LEN] = 0;
+  tstrncpy(name, &tableId[s1 + s2 + 2], TSDB_TABLE_NAME_LEN);
 }
 
 char* extractDBName(const char* tableId, char* name) {
diff --git a/src/connector/python/linux/python3/taos/cinterface.py b/src/connector/python/linux/python3/taos/cinterface.py
index c3c8a4603a..568e73e355 100644
--- a/src/connector/python/linux/python3/taos/cinterface.py
+++ b/src/connector/python/linux/python3/taos/cinterface.py
@@ -130,9 +130,9 @@ _CONVERT_FUNC = {
 
 # Corresponding TAOS_FIELD structure in C
 class TaosField(ctypes.Structure):
-    _fields_ = [('name', ctypes.c_char * 64),
-                ('bytes', ctypes.c_short),
-                ('type', ctypes.c_char)]
+    _fields_ = [('name', ctypes.c_char * 65),
+                ('type', ctypes.c_char),
+                ('bytes', ctypes.c_short)]
 
 # C interface class
 class CTaosInterface(object):
diff --git a/src/inc/taos.h b/src/inc/taos.h
index 947cbe6759..bf6942be8b 100644
--- a/src/inc/taos.h
+++ b/src/inc/taos.h
@@ -53,9 +53,9 @@ typedef enum {
 } TSDB_OPTION;
 
 typedef struct taosField {
-  char     name[64];
-  short    bytes;
+  char     name[65];
   uint8_t  type;
+  short    bytes;
 } TAOS_FIELD;
 
 #ifdef _TD_GO_DLL_
diff --git a/src/inc/taosdef.h b/src/inc/taosdef.h
index c75fc70d75..1e0ddf0f9f 100644
--- a/src/inc/taosdef.h
+++ b/src/inc/taosdef.h
@@ -189,7 +189,7 @@ void tsDataSwap(void *pLeft, void *pRight, int32_t type, int32_t size);
 #define TSDB_USERID_LEN           9
 #define TS_PATH_DELIMITER_LEN     1
 
-#define TSDB_METER_ID_LEN_MARGIN  10
+#define TSDB_METER_ID_LEN_MARGIN  8
 #define TSDB_TABLE_ID_LEN         (TSDB_DB_NAME_LEN+TSDB_TABLE_NAME_LEN+2*TS_PATH_DELIMITER_LEN+TSDB_USERID_LEN+TSDB_METER_ID_LEN_MARGIN) //TSDB_DB_NAME_LEN+TSDB_TABLE_NAME_LEN+2*strlen(TS_PATH_DELIMITER)+strlen(USERID)
 #define TSDB_UNI_LEN              24
 #define TSDB_USER_LEN             TSDB_UNI_LEN
@@ -200,9 +200,9 @@ void tsDataSwap(void *pLeft, void *pRight, int32_t type, int32_t size);
 #define TSDB_MIN_COLUMNS          2       //PRIMARY COLUMN(timestamp) + other columns
 
 #define TSDB_NODE_NAME_LEN        64
-#define TSDB_TABLE_NAME_LEN       192
-#define TSDB_DB_NAME_LEN          32
-#define TSDB_COL_NAME_LEN         64
+#define TSDB_TABLE_NAME_LEN       193
+#define TSDB_DB_NAME_LEN          33
+#define TSDB_COL_NAME_LEN         65
 #define TSDB_MAX_SAVED_SQL_LEN    TSDB_MAX_COLUMNS * 64
 #define TSDB_MAX_SQL_LEN          TSDB_PAYLOAD_SIZE
 #define TSDB_MAX_SQL_SHOW_LEN     256
diff --git a/src/inc/taosmsg.h b/src/inc/taosmsg.h
index 88c6f9cf26..dca8287394 100644
--- a/src/inc/taosmsg.h
+++ b/src/inc/taosmsg.h
@@ -224,7 +224,7 @@ typedef struct {
 
 typedef struct SSchema {
   uint8_t type;
-  char    name[TSDB_COL_NAME_LEN + 1];
+  char    name[TSDB_COL_NAME_LEN];
   int16_t colId;
   int16_t bytes;
 } SSchema;
@@ -250,7 +250,7 @@ typedef struct {
 
 typedef struct {
   char    tableId[TSDB_TABLE_ID_LEN + 1];
-  char    db[TSDB_DB_NAME_LEN + 1];
+  char    db[TSDB_DB_NAME_LEN];
   int8_t  igExists;
   int8_t  getMeta;
   int16_t numOfTags;
@@ -268,7 +268,7 @@ typedef struct {
 
 typedef struct {
   char    tableId[TSDB_TABLE_ID_LEN + 1];
-  char    db[TSDB_DB_NAME_LEN + 1];
+  char    db[TSDB_DB_NAME_LEN];
   int16_t type; /* operation type   */
   int16_t numOfCols; /* number of schema */
   int32_t tagValLen;
@@ -502,7 +502,7 @@ typedef struct {
 
 typedef struct {
   char     acct[TSDB_USER_LEN + 1];
-  char     db[TSDB_DB_NAME_LEN + 1];
+  char     db[TSDB_DB_NAME_LEN];
   int32_t  cacheBlockSize; //MB
   int32_t  totalBlocks;
   int32_t  maxTables;
@@ -606,7 +606,7 @@ typedef struct {
 } SMDVnodeDesc;
 
 typedef struct {
-  char db[TSDB_DB_NAME_LEN + 1];
+  char db[TSDB_DB_NAME_LEN];
   SMDVnodeCfg  cfg;
   SMDVnodeDesc nodes[TSDB_MAX_REPLICA];
 } SMDCreateVnodeMsg;
@@ -671,7 +671,7 @@ typedef struct {
  */
 typedef struct {
   int8_t   type;
-  char     db[TSDB_DB_NAME_LEN + 1];
+  char     db[TSDB_DB_NAME_LEN];
   uint16_t payloadLen;
   char     payload[];
 } SCMShowMsg;
diff --git a/src/kit/taosdump/taosdump.c b/src/kit/taosdump/taosdump.c
index d96f80ed20..417de629aa 100644
--- a/src/kit/taosdump/taosdump.c
+++ b/src/kit/taosdump/taosdump.c
@@ -88,21 +88,21 @@ enum _describe_table_index {
 };
 
 typedef struct {
-  char field[TSDB_COL_NAME_LEN + 1];
+  char field[TSDB_COL_NAME_LEN];
   char type[16];
   int length;
   char note[128];
 } SColDes;
 
 typedef struct {
-  char name[TSDB_COL_NAME_LEN + 1];
+  char name[TSDB_COL_NAME_LEN];
   SColDes cols[];
 } STableDef;
 
 extern char version[];
 
 typedef struct {
-  char name[TSDB_DB_NAME_LEN + 1];
+  char name[TSDB_DB_NAME_LEN];
   int32_t replica;
   int32_t days;
   int32_t keep;
diff --git a/src/mnode/inc/mnodeDef.h b/src/mnode/inc/mnodeDef.h
index cf9058b9cf..35ae9aad33 100644
--- a/src/mnode/inc/mnodeDef.h
+++ b/src/mnode/inc/mnodeDef.h
@@ -115,7 +115,7 @@ typedef struct {
 
 typedef struct SVgObj {
   uint32_t       vgId;
-  char           dbName[TSDB_DB_NAME_LEN + 1];
+  char           dbName[TSDB_DB_NAME_LEN];
   int64_t        createdTime;
   SVnodeGid      vnodeGid[TSDB_MAX_REPLICA];
   int32_t        numOfVnodes;
@@ -154,7 +154,7 @@ typedef struct {
 } SDbCfg;
 
 typedef struct SDbObj {
-  char    name[TSDB_DB_NAME_LEN + 1];
+  char    name[TSDB_DB_NAME_LEN];
   char    acct[TSDB_USER_LEN + 1];
   int64_t createdTime;
   int32_t cfgVersion;
@@ -219,7 +219,7 @@ typedef struct SAcctObj {
 typedef struct {
   int8_t   type;
   int32_t  index;
-  char     db[TSDB_DB_NAME_LEN + 1];
+  char     db[TSDB_DB_NAME_LEN];
   void *   pIter;
   int16_t  numOfColumns;
   int32_t  rowSize;
diff --git a/src/mnode/src/mnodeDb.c b/src/mnode/src/mnodeDb.c
index 90569b4a95..c80dc3036f 100644
--- a/src/mnode/src/mnodeDb.c
+++ b/src/mnode/src/mnodeDb.c
@@ -328,8 +328,8 @@ static int32_t mnodeCreateDb(SAcctObj *pAcct, SCMCreateDbMsg *pCreate) {
   if (code != 0) return code;
 
   pDb = calloc(1, sizeof(SDbObj));
-  strncpy(pDb->name, pCreate->db, TSDB_DB_NAME_LEN);
-  strncpy(pDb->acct, pAcct->user, TSDB_USER_LEN); 
+  tstrncpy(pDb->name, pCreate->db, sizeof(pDb->name));
+  tstrncpy(pDb->acct, pAcct->user, sizeof(pDb->acct)); 
   pDb->createdTime = taosGetTimestampMs(); 
   pDb->cfg = (SDbCfg) {
     .cacheBlockSize      = pCreate->cacheBlockSize,
@@ -373,7 +373,7 @@ static int32_t mnodeCreateDb(SAcctObj *pAcct, SCMCreateDbMsg *pCreate) {
 }
 
 bool mnodeCheckIsMonitorDB(char *db, char *monitordb) {
-  char dbName[TSDB_DB_NAME_LEN + 1] = {0};
+  char dbName[TSDB_DB_NAME_LEN] = {0};
   extractDBName(db, dbName);
 
   size_t len = strlen(dbName);
@@ -453,7 +453,7 @@ static int32_t mnodeGetDbMeta(STableMetaMsg *pMeta, SShowObj *pShow, void *pConn
   SUserObj *pUser = mnodeGetUserFromConn(pConn);
   if (pUser == NULL) return 0;
 
-  pShow->bytes[cols] = TSDB_DB_NAME_LEN + VARSTR_HEADER_SIZE;
+  pShow->bytes[cols] = (TSDB_DB_NAME_LEN - 1) + VARSTR_HEADER_SIZE;
   pSchema[cols].type = TSDB_DATA_TYPE_BINARY;
   strcpy(pSchema[cols].name, "name");
   pSchema[cols].bytes = htons(pShow->bytes[cols]);
@@ -610,7 +610,7 @@ static int32_t mnodeRetrieveDbs(SShowObj *pShow, char *data, int32_t rows, void
     pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
     
     char* name = mnodeGetDbStr(pDb->name);
-    STR_WITH_MAXSIZE_TO_VARSTR(pWrite, name, TSDB_DB_NAME_LEN);
+    STR_WITH_MAXSIZE_TO_VARSTR(pWrite, name, TSDB_DB_NAME_LEN - 1);
     cols++;
 
     pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
diff --git a/src/mnode/src/mnodeSdb.c b/src/mnode/src/mnodeSdb.c
index b9033cdf3c..8d74827841 100644
--- a/src/mnode/src/mnodeSdb.c
+++ b/src/mnode/src/mnodeSdb.c
@@ -43,7 +43,7 @@ typedef enum {
 } ESdbStatus;
 
 typedef struct _SSdbTable {
-  char      tableName[TSDB_DB_NAME_LEN + 1];
+  char      tableName[TSDB_DB_NAME_LEN];
   ESdbTable tableId;
   ESdbKey   keyType;
   int32_t   hashSessions;
diff --git a/src/mnode/src/mnodeTable.c b/src/mnode/src/mnodeTable.c
index 119ba1627d..cde94c39b5 100644
--- a/src/mnode/src/mnodeTable.c
+++ b/src/mnode/src/mnodeTable.c
@@ -951,7 +951,7 @@ static int32_t mnodeModifySuperTableTagName(SSuperTableObj *pStable, char *oldTa
 
   // update
   SSchema *schema = (SSchema *) (pStable->schema + pStable->numOfColumns + col);
-  strncpy(schema->name, newTagName, TSDB_COL_NAME_LEN);
+  tstrncpy(schema->name, newTagName, sizeof(schema->name));
 
   SSdbOper oper = {
     .type = SDB_OPER_GLOBAL,
@@ -1078,7 +1078,7 @@ static int32_t mnodeGetShowSuperTableMeta(STableMetaMsg *pMeta, SShowObj *pShow,
   int32_t cols = 0;
   SSchema *pSchema = pMeta->schema;
 
-  pShow->bytes[cols] = TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE;
+  pShow->bytes[cols] = (TSDB_TABLE_NAME_LEN - 1) + VARSTR_HEADER_SIZE;
   pSchema[cols].type = TSDB_DATA_TYPE_BINARY;
   strcpy(pSchema[cols].name, "name");
   pSchema[cols].bytes = htons(pShow->bytes[cols]);
@@ -1138,7 +1138,7 @@ int32_t mnodeRetrieveShowSuperTables(SShowObj *pShow, char *data, int32_t rows,
   prefixLen = strlen(prefix);
 
   SPatternCompareInfo info = PATTERN_COMPARE_INFO_INITIALIZER;
-  char stableName[TSDB_TABLE_NAME_LEN + 1] = {0};
+  char stableName[TSDB_TABLE_NAME_LEN] = {0};
 
   while (numOfRows < rows) {    
     pShow->pIter = mnodeGetNextSuperTable(pShow->pIter, &pTable);
@@ -1151,7 +1151,7 @@ int32_t mnodeRetrieveShowSuperTables(SShowObj *pShow, char *data, int32_t rows,
     memset(stableName, 0, tListLen(stableName));
     mnodeExtractTableName(pTable->info.tableId, stableName);
 
-    if (pShow->payloadLen > 0 && patternMatch(pShow->payload, stableName, TSDB_TABLE_NAME_LEN, &info) != TSDB_PATTERN_MATCH) {
+    if (pShow->payloadLen > 0 && patternMatch(pShow->payload, stableName, sizeof(stableName) - 1, &info) != TSDB_PATTERN_MATCH) {
       mnodeDecTableRef(pTable);
       continue;
     }
@@ -1160,7 +1160,7 @@ int32_t mnodeRetrieveShowSuperTables(SShowObj *pShow, char *data, int32_t rows,
 
     pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
   
-    int16_t len = strnlen(stableName, TSDB_DB_NAME_LEN);
+    int16_t len = strnlen(stableName, TSDB_DB_NAME_LEN - 1);
     *(int16_t*) pWrite = len;
     pWrite += sizeof(int16_t); // todo refactor
   
@@ -1228,7 +1228,7 @@ static int32_t mnodeSetSchemaFromSuperTable(SSchema *pSchema, SSuperTableObj *pT
   assert(numOfCols <= TSDB_MAX_COLUMNS);
   
   for (int32_t i = 0; i < numOfCols; ++i) {
-    strncpy(pSchema->name, pTable->schema[i].name, TSDB_COL_NAME_LEN);
+    tstrncpy(pSchema->name, pTable->schema[i].name, sizeof(pSchema->name));
     pSchema->type  = pTable->schema[i].type;
     pSchema->bytes = htons(pTable->schema[i].bytes);
     pSchema->colId = htons(pTable->schema[i].colId);
@@ -2079,7 +2079,7 @@ static int32_t mnodeGetShowTableMeta(STableMetaMsg *pMeta, SShowObj *pShow, void
   int32_t cols = 0;
   SSchema *pSchema = pMeta->schema;
 
-  pShow->bytes[cols] = TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE;
+  pShow->bytes[cols] = (TSDB_TABLE_NAME_LEN - 1) + VARSTR_HEADER_SIZE;
   pSchema[cols].type = TSDB_DATA_TYPE_BINARY;
   strcpy(pSchema[cols].name, "table_name");
   pSchema[cols].bytes = htons(pShow->bytes[cols]);
@@ -2097,7 +2097,7 @@ static int32_t mnodeGetShowTableMeta(STableMetaMsg *pMeta, SShowObj *pShow, void
   pSchema[cols].bytes = htons(pShow->bytes[cols]);
   cols++;
 
-  pShow->bytes[cols] = TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE;
+  pShow->bytes[cols] = (TSDB_TABLE_NAME_LEN - 1) + VARSTR_HEADER_SIZE;
   pSchema[cols].type = TSDB_DATA_TYPE_BINARY;
   strcpy(pSchema[cols].name, "stable_name");
   pSchema[cols].bytes = htons(pShow->bytes[cols]);
@@ -2141,12 +2141,12 @@ static int32_t mnodeRetrieveShowTables(SShowObj *pShow, char *data, int32_t rows
       continue;
     }
 
-    char tableName[TSDB_TABLE_NAME_LEN + 1] = {0};
+    char tableName[TSDB_TABLE_NAME_LEN] = {0};
     
     // pattern compare for table name
     mnodeExtractTableName(pTable->info.tableId, tableName);
 
-    if (pShow->payloadLen > 0 && patternMatch(pShow->payload, tableName, TSDB_TABLE_NAME_LEN, &info) != TSDB_PATTERN_MATCH) {
+    if (pShow->payloadLen > 0 && patternMatch(pShow->payload, tableName, sizeof(tableName) - 1, &info) != TSDB_PATTERN_MATCH) {
       mnodeDecTableRef(pTable);
       continue;
     }
@@ -2155,7 +2155,7 @@ static int32_t mnodeRetrieveShowTables(SShowObj *pShow, char *data, int32_t rows
 
     char *pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
 
-    STR_WITH_MAXSIZE_TO_VARSTR(pWrite, tableName, TSDB_TABLE_NAME_LEN);
+    STR_WITH_MAXSIZE_TO_VARSTR(pWrite, tableName, sizeof(tableName) - 1);
     cols++;
 
     pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
@@ -2173,10 +2173,10 @@ static int32_t mnodeRetrieveShowTables(SShowObj *pShow, char *data, int32_t rows
 
     pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
     
-    memset(tableName, 0, tListLen(tableName));
+    memset(tableName, 0, sizeof(tableName));
     if (pTable->info.type == TSDB_CHILD_TABLE) {
       mnodeExtractTableName(pTable->superTable->info.tableId, tableName);
-      STR_WITH_MAXSIZE_TO_VARSTR(pWrite, tableName, TSDB_TABLE_NAME_LEN);
+      STR_WITH_MAXSIZE_TO_VARSTR(pWrite, tableName, sizeof(tableName) - 1);
     }
     
     cols++;
@@ -2268,7 +2268,7 @@ static int32_t mnodeGetStreamTableMeta(STableMetaMsg *pMeta, SShowObj *pShow, vo
   int32_t cols = 0;
   SSchema *pSchema = pMeta->schema;
 
-  pShow->bytes[cols] = TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE;
+  pShow->bytes[cols] = (TSDB_TABLE_NAME_LEN - 1) + VARSTR_HEADER_SIZE;
   pSchema[cols].type = TSDB_DATA_TYPE_BINARY;
   strcpy(pSchema[cols].name, "table_name");
   pSchema[cols].bytes = htons(pShow->bytes[cols]);
@@ -2331,12 +2331,12 @@ static int32_t mnodeRetrieveStreamTables(SShowObj *pShow, char *data, int32_t ro
       continue;
     }
 
-    char tableName[TSDB_TABLE_NAME_LEN + 1] = {0};
+    char tableName[TSDB_TABLE_NAME_LEN] = {0};
     
     // pattern compare for table name
     mnodeExtractTableName(pTable->info.tableId, tableName);
 
-    if (pShow->payloadLen > 0 && patternMatch(pShow->payload, tableName, TSDB_TABLE_NAME_LEN, &info) != TSDB_PATTERN_MATCH) {
+    if (pShow->payloadLen > 0 && patternMatch(pShow->payload, tableName, sizeof(tableName) - 1, &info) != TSDB_PATTERN_MATCH) {
       mnodeDecTableRef(pTable);
       continue;
     }
@@ -2345,7 +2345,7 @@ static int32_t mnodeRetrieveStreamTables(SShowObj *pShow, char *data, int32_t ro
 
     char *pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
 
-    STR_WITH_MAXSIZE_TO_VARSTR(pWrite, tableName, TSDB_TABLE_NAME_LEN);
+    STR_WITH_MAXSIZE_TO_VARSTR(pWrite, tableName, sizeof(tableName) - 1);
     cols++;
 
     pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
diff --git a/src/os/darwin/src/darwinPlatform.c b/src/os/darwin/src/darwinPlatform.c
index 05290c43f4..cae65a2927 100644
--- a/src/os/darwin/src/darwinPlatform.c
+++ b/src/os/darwin/src/darwinPlatform.c
@@ -189,7 +189,7 @@ void taosGetSystemLocale() {
   if (cfg_locale && cfg_locale->cfgStatus < TAOS_CFG_CSTATUS_DEFAULT) {
     char *locale = setlocale(LC_CTYPE, "chs");
     if (locale != NULL) {
-      strncpy(tsLocale, locale, sizeof(tsLocale) / sizeof(tsLocale[0]));
+      tstrncpy(tsLocale, locale, sizeof(tsLocale));
       cfg_locale->cfgStatus = TAOS_CFG_CSTATUS_DEFAULT;
       uPrint("locale not configured, set to default:%s", tsLocale);
     }
diff --git a/src/os/linux/src/linuxSysPara.c b/src/os/linux/src/linuxSysPara.c
index b270eb14cf..3ec7de3b63 100644
--- a/src/os/linux/src/linuxSysPara.c
+++ b/src/os/linux/src/linuxSysPara.c
@@ -229,7 +229,7 @@ static void taosGetSystemLocale() {  // get and set default locale
       uError("can't get locale from system, set it to en_US.UTF-8");
       strcpy(tsLocale, "en_US.UTF-8");
     } else {
-      tstrncpy(tsLocale, locale, tListLen(tsLocale));
+      tstrncpy(tsLocale, locale, sizeof(tsLocale));
       uError("locale not configured, set to system default:%s", tsLocale);
     }
   }
@@ -242,7 +242,7 @@ static void taosGetSystemLocale() {  // get and set default locale
       str++;
 
       char *revisedCharset = taosCharsetReplace(str);
-      strncpy(tsCharset, revisedCharset, tListLen(tsCharset));
+      tstrncpy(tsCharset, revisedCharset, sizeof(tsCharset));
 
       free(revisedCharset);
       uWarn("charset not configured, set to system default:%s", tsCharset);
diff --git a/src/os/windows/src/twindows.c b/src/os/windows/src/twindows.c
index 76b354f784..82bcc69b11 100644
--- a/src/os/windows/src/twindows.c
+++ b/src/os/windows/src/twindows.c
@@ -226,7 +226,7 @@ void taosGetSystemLocale() {
   if (cfg_locale && cfg_locale->cfgStatus < TAOS_CFG_CSTATUS_DEFAULT) {
     char *locale = setlocale(LC_CTYPE, "chs");
     if (locale != NULL) {
-      strncpy(tsLocale, locale, sizeof(tsLocale) / sizeof(tsLocale[0]));
+      tstrncpy(tsLocale, locale, sizeof(tsLocale));
       cfg_locale->cfgStatus = TAOS_CFG_CSTATUS_DEFAULT;
       uPrint("locale not configured, set to default:%s", tsLocale);
     }
diff --git a/src/plugins/http/src/httpUtil.c b/src/plugins/http/src/httpUtil.c
index b91b89e21c..1fb63ea2fc 100644
--- a/src/plugins/http/src/httpUtil.c
+++ b/src/plugins/http/src/httpUtil.c
@@ -307,7 +307,7 @@ void httpTrimTableName(char *name) {
   for (int i = 0; name[i] != 0; i++) {
     if (name[i] == ' ' || name[i] == ':' || name[i] == '.' || name[i] == '-' || name[i] == '/' || name[i] == '\'')
       name[i] = '_';
-    if (i == TSDB_TABLE_NAME_LEN + 1) {
+    if (i == TSDB_TABLE_NAME_LEN) {
       name[i] = 0;
       break;
     }
@@ -323,7 +323,7 @@ int httpShrinkTableName(HttpContext *pContext, int pos, char *name) {
     len++;
   }
 
-  if (len < TSDB_TABLE_NAME_LEN) {
+  if (len < TSDB_TABLE_NAME_LEN - 1) {
     return pos;
   }
 
diff --git a/src/plugins/http/src/tgHandle.c b/src/plugins/http/src/tgHandle.c
index c6a2230bfb..945eff7611 100644
--- a/src/plugins/http/src/tgHandle.c
+++ b/src/plugins/http/src/tgHandle.c
@@ -209,7 +209,7 @@ void tgParseSchemaMetric(cJSON *metric) {
         goto ParseEnd;
       }
       int nameLen = (int)strlen(field->valuestring);
-      if (nameLen == 0 || nameLen > TSDB_TABLE_NAME_LEN) {
+      if (nameLen == 0 || nameLen >= TSDB_TABLE_NAME_LEN) {
         parsedOk = false;
         goto ParseEnd;
       }
@@ -409,7 +409,7 @@ bool tgProcessSingleMetric(HttpContext *pContext, cJSON *metric, char *db) {
     httpSendErrorResp(pContext, HTTP_TG_METRIC_NAME_NULL);
     return false;
   }
-  if (nameLen >= TSDB_TABLE_NAME_LEN - 7) {
+  if (nameLen >= TSDB_TABLE_NAME_LEN - 8) {
     httpSendErrorResp(pContext, HTTP_TG_METRIC_NAME_LONG);
     return false;
   }
@@ -498,7 +498,7 @@ bool tgProcessSingleMetric(HttpContext *pContext, cJSON *metric, char *db) {
     return false;
   }
 
-  if (strlen(host->valuestring) >= TSDB_TABLE_NAME_LEN) {
+  if (strlen(host->valuestring) >= TSDB_TABLE_NAME_LEN - 1) {
     httpSendErrorResp(pContext, HTTP_TG_TABLE_SIZE);
     return false;
   }
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 26502a7408..92c23f6b83 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -1368,7 +1368,7 @@ static int32_t setupQueryRuntimeEnv(SQueryRuntimeEnv *pRuntimeEnv, int16_t order
     int32_t index = pSqlFuncMsg->colInfo.colIndex;
     if (TSDB_COL_IS_TAG(pIndex->flag)) {
       if (pIndex->colId == TSDB_TBNAME_COLUMN_INDEX) {  // todo refactor
-        pCtx->inputBytes = TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE;
+        pCtx->inputBytes = (TSDB_TABLE_NAME_LEN - 1) + VARSTR_HEADER_SIZE;
         pCtx->inputType = TSDB_DATA_TYPE_BINARY;
       } else {
         pCtx->inputBytes = pQuery->tagColList[index].bytes;
@@ -5148,8 +5148,8 @@ static int32_t createQFunctionExprFromMsg(SQueryTableMsg *pQueryMsg, SExprInfo *
       bytes = tDataTypeDesc[type].nSize;
     } else if (pExprs[i].base.colInfo.colId == TSDB_TBNAME_COLUMN_INDEX && pExprs[i].base.functionId == TSDB_FUNC_TAGPRJ) {  // parse the normal column
       type  = TSDB_DATA_TYPE_BINARY;
-      bytes = TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE;
-    } else {
+      bytes = (TSDB_TABLE_NAME_LEN - 1) + VARSTR_HEADER_SIZE;
+    } else{
       int32_t j = getColumnIndexInSource(pQueryMsg, &pExprs[i].base, pTagCols);
       assert(j < pQueryMsg->numOfCols || j < pQueryMsg->numOfTags || j == TSDB_TBNAME_COLUMN_INDEX);
 
@@ -6038,7 +6038,7 @@ static void buildTagQueryResult(SQInfo* pQInfo) {
       for(int32_t j = 0; j < pQuery->numOfOutput; ++j) {
         if (pExprInfo[j].base.colInfo.colId == TSDB_TBNAME_COLUMN_INDEX) {
           char* data = tsdbGetTableName(pQInfo->tsdb, &item->id);
-          char* dst = pQuery->sdata[j]->data + count * (TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE);
+          char* dst = pQuery->sdata[j]->data + count * ((TSDB_TABLE_NAME_LEN - 1) + VARSTR_HEADER_SIZE);
           memcpy(dst, data, varDataTLen(data));
         } else {// todo refactor
           int16_t type = pExprInfo[j].type;
diff --git a/src/query/src/qast.c b/src/query/src/qast.c
index 0a0fe56ebd..1db965e8a3 100644
--- a/src/query/src/qast.c
+++ b/src/query/src/qast.c
@@ -138,7 +138,7 @@ static tExprNode *tExprNodeCreate(SSchema *pSchema, int32_t numOfCols, SSQLToken
       memcpy(pNode->pSchema, &pSchema[i], sizeof(SSchema));
     } else {
       pNode->pSchema->type = TSDB_DATA_TYPE_BINARY;
-      pNode->pSchema->bytes = TSDB_TABLE_NAME_LEN;
+      pNode->pSchema->bytes = TSDB_TABLE_NAME_LEN - 1;
       strcpy(pNode->pSchema->name, TSQL_TBNAME_L);
       pNode->pSchema->colId = -1;
     }
@@ -1127,7 +1127,7 @@ tExprNode* exprTreeFromTableName(const char* tbnameCond) {
   left->pSchema = pSchema;
 
   pSchema->type = TSDB_DATA_TYPE_BINARY;
-  pSchema->bytes = TSDB_TABLE_NAME_LEN;
+  pSchema->bytes = TSDB_TABLE_NAME_LEN - 1;
   strcpy(pSchema->name, TSQL_TBNAME_L);
   pSchema->colId = -1;
 
diff --git a/src/query/src/qtsbuf.c b/src/query/src/qtsbuf.c
index 555ccb7318..869299f309 100644
--- a/src/query/src/qtsbuf.c
+++ b/src/query/src/qtsbuf.c
@@ -51,7 +51,7 @@ STSBuf* tsBufCreateFromFile(const char* path, bool autoDelete) {
     return NULL;
   }
   
-  strncpy(pTSBuf->path, path, PATH_MAX);
+  tstrncpy(pTSBuf->path, path, sizeof(pTSBuf->path));
   
   pTSBuf->f = fopen(pTSBuf->path, "r+");
   if (pTSBuf->f == NULL) {
diff --git a/src/rpc/src/rpcMain.c b/src/rpc/src/rpcMain.c
index b0a5a0bfc0..6044061127 100644
--- a/src/rpc/src/rpcMain.c
+++ b/src/rpc/src/rpcMain.c
@@ -458,7 +458,7 @@ int rpcGetConnInfo(void *thandle, SRpcConnInfo *pInfo) {
   pInfo->clientPort = pConn->peerPort;
   // pInfo->serverIp = pConn->destIp;
 
-  strncpy(pInfo->user, pConn->user, sizeof(pInfo->user));
+  tstrncpy(pInfo->user, pConn->user, sizeof(pInfo->user));
   return 0;
 }
 
diff --git a/src/tsdb/src/tsdbMeta.c b/src/tsdb/src/tsdbMeta.c
index 40e5667893..8eb259d38c 100644
--- a/src/tsdb/src/tsdbMeta.c
+++ b/src/tsdb/src/tsdbMeta.c
@@ -334,7 +334,7 @@ static STable *tsdbNewTable(STableCfg *pCfg, bool isSuper) {
     pTable->schema[0] = tdDupSchema(pCfg->schema);
     pTable->tagSchema = tdDupSchema(pCfg->tagSchema);
 
-    tsize = strnlen(pCfg->sname, TSDB_TABLE_NAME_LEN);
+    tsize = strnlen(pCfg->sname, TSDB_TABLE_NAME_LEN - 1);
     pTable->name = calloc(1, tsize + VARSTR_HEADER_SIZE + 1);
     if (pTable->name == NULL) {
       terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
@@ -355,7 +355,7 @@ static STable *tsdbNewTable(STableCfg *pCfg, bool isSuper) {
     pTable->tableId.tid = pCfg->tableId.tid;
     pTable->lastKey = TSKEY_INITIAL_VAL;
 
-    tsize = strnlen(pCfg->name, TSDB_TABLE_NAME_LEN);
+    tsize = strnlen(pCfg->name, TSDB_TABLE_NAME_LEN - 1);
     pTable->name = calloc(1, tsize + VARSTR_HEADER_SIZE + 1);
     if (pTable->name == NULL) {
       terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
diff --git a/src/tsdb/src/tsdbRead.c b/src/tsdb/src/tsdbRead.c
index 86ce44ad7b..d3a909a162 100644
--- a/src/tsdb/src/tsdbRead.c
+++ b/src/tsdb/src/tsdbRead.c
@@ -2011,7 +2011,7 @@ int32_t tableGroupComparFn(const void *p1, const void *p2, const void *param) {
       f1 = (char*) pTable1->name;
       f2 = (char*) pTable2->name;
       type = TSDB_DATA_TYPE_BINARY;
-      bytes = TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE;
+      bytes = (TSDB_TABLE_NAME_LEN - 1) + VARSTR_HEADER_SIZE;
     } else {
       STColumn* pCol = schemaColAt(pTableGroupSupp->pTagSchema, colIndex);
       bytes = pCol->bytes;
diff --git a/src/util/src/tsched.c b/src/util/src/tsched.c
index 898ab70876..6fc767fd3b 100644
--- a/src/util/src/tsched.c
+++ b/src/util/src/tsched.c
@@ -15,6 +15,7 @@
 
 #include "os.h"
 #include "taosdef.h"
+#include "tutil.h"
 #include "tulog.h"
 #include "tsched.h"
 #include "ttimer.h"
@@ -62,8 +63,7 @@ void *taosInitScheduler(int queueSize, int numOfThreads, const char *label) {
   }
 
   pSched->queueSize = queueSize;
-  strncpy(pSched->label, label, sizeof(pSched->label)); // fix buffer overflow
-  pSched->label[sizeof(pSched->label)-1] = '\0';
+  tstrncpy(pSched->label, label, sizeof(pSched->label)); // fix buffer overflow
 
   pSched->fullSlot = 0;
   pSched->emptySlot = 0;
diff --git a/src/util/src/ttimer.c b/src/util/src/ttimer.c
index 68db574d82..cdb2c6c0be 100644
--- a/src/util/src/ttimer.c
+++ b/src/util/src/ttimer.c
@@ -552,8 +552,7 @@ void* taosTmrInit(int maxNumOfTmrs, int resolution, int longest, const char* lab
     return NULL;
   }
 
-  strncpy(ctrl->label, label, sizeof(ctrl->label));
-  ctrl->label[sizeof(ctrl->label) - 1] = 0;
+  tstrncpy(ctrl->label, label, sizeof(ctrl->label));
   tmrTrace("%s timer controller is initialized, number of timer controllers: %d.", label, numOfTmrCtrl);
   return ctrl;
 }
diff --git a/src/util/src/tutil.c b/src/util/src/tutil.c
index c524a61591..9209117415 100644
--- a/src/util/src/tutil.c
+++ b/src/util/src/tutil.c
@@ -582,13 +582,13 @@ bool taosGetVersionNumber(char *versionStr, int *versionNubmer) {
 }
 
 int taosCheckVersion(char *input_client_version, char *input_server_version, int comparedSegments) {
-  char client_version[64] = {0};
-  char server_version[64] = {0};
+  char client_version[TSDB_VERSION_LEN] = {0};
+  char server_version[TSDB_VERSION_LEN] = {0};
   int clientVersionNumber[4] = {0};
   int serverVersionNumber[4] = {0};
 
-  strcpy(client_version, input_client_version);
-  strcpy(server_version, input_server_version);
+  tstrncpy(client_version, input_client_version, sizeof(client_version));
+  tstrncpy(server_version, input_server_version, sizeof(server_version));
 
   if (!taosGetVersionNumber(client_version, clientVersionNumber)) {
     uError("invalid client version:%s", client_version);
diff --git a/src/vnode/inc/vnodeInt.h b/src/vnode/inc/vnodeInt.h
index 7c95e81cf5..ab74e329e6 100644
--- a/src/vnode/inc/vnodeInt.h
+++ b/src/vnode/inc/vnodeInt.h
@@ -51,7 +51,7 @@ typedef struct {
   SSyncCfg     syncCfg;
   SWalCfg      walCfg;
   char        *rootDir;
-  char         db[TSDB_DB_NAME_LEN + 1];
+  char         db[TSDB_DB_NAME_LEN];
 } SVnodeObj;
 
 int  vnodeWriteToQueue(void *param, void *pHead, int type);
diff --git a/tests/pytest/table/boundary.py b/tests/pytest/table/boundary.py
index bb5e187f0d..d9f0490ed4 100644
--- a/tests/pytest/table/boundary.py
+++ b/tests/pytest/table/boundary.py
@@ -96,14 +96,14 @@ class TDTestCase:
         tdLog.notice("table name max length is %d" % maxTableNameLen)
 
         # create a super table with name exceed max length
-        sname = self.generateString(maxTableNameLen + 1)
+        sname = self.generateString(maxTableNameLen)
         tdLog.info("create a super table with length %d" % len(sname))
         tdSql.error(
             "create table %s (ts timestamp, value int) tags(id int)" %
             sname)
 
         # create a super table with name of max length
-        sname = self.generateString(maxTableNameLen)
+        sname = self.generateString(maxTableNameLen - 1)
         tdLog.info("create a super table with length %d" % len(sname))
         tdSql.execute(
             "create table %s (ts timestamp, value int) tags(id int)" %
@@ -113,12 +113,12 @@ class TDTestCase:
         tdSql.checkRows(1)
 
         # create a child table with name exceed max length
-        name = self.generateString(maxTableNameLen + 1)
+        name = self.generateString(maxTableNameLen)
         tdLog.info("create a child table with length %d" % len(name))
         tdSql.error("create table %s using %s tags(0)" % (name, sname))
 
         # create a child table with name of max length
-        name = self.generateString(maxTableNameLen)
+        name = self.generateString(maxTableNameLen - 1)
         tdLog.info("create a child table with length %d" % len(name))
         tdSql.execute("create table %s using %s tags(0)" % (name, sname))
         tdSql.query('show tables')
diff --git a/tests/pytest/table/tablename-boundary.py b/tests/pytest/table/tablename-boundary.py
index ce843c3fe7..6ce986c51e 100644
--- a/tests/pytest/table/tablename-boundary.py
+++ b/tests/pytest/table/tablename-boundary.py
@@ -18,9 +18,7 @@ class TDTestCase:
         tdSql.prepare()
 
         getTableNameLen = "grep -w '#define TSDB_TABLE_NAME_LEN' ../../src/inc/taosdef.h|awk '{print $3}'"
-        tableNameMaxLen = int(
-            subprocess.check_output(
-                getTableNameLen, shell=True))
+        tableNameMaxLen = int( subprocess.check_output(getTableNameLen, shell=True)) - 1
         tdLog.info("table name max length is %d" % tableNameMaxLen)
         chars = string.ascii_uppercase + string.ascii_lowercase
         tb_name = ''.join(random.choices(chars, k=tableNameMaxLen))
diff --git a/tests/tsim/src/simParse.c b/tests/tsim/src/simParse.c
index fddda679c6..9fea1f115b 100644
--- a/tests/tsim/src/simParse.c
+++ b/tests/tsim/src/simParse.c
@@ -165,7 +165,7 @@ SScript *simBuildScriptObj(char *fileName) {
 
   script->type = SIM_SCRIPT_TYPE_MAIN;
   script->numOfLines = numOfLines;
-  strncpy(script->fileName, fileName, MAX_FILE_NAME_LEN);
+  tstrncpy(script->fileName, fileName, sizeof(script->fileName));
 
   script->optionBuffer = malloc(optionOffset);
   memcpy(script->optionBuffer, optionBuffer, optionOffset);