diff --git a/cmake/version.inc b/cmake/version.inc
index f576627908721da5a2e3e69a02e7ba405d47e3a7..20be64147c9a4506924d0f388bea1f0d140c017f 100755
--- a/cmake/version.inc
+++ b/cmake/version.inc
@@ -4,7 +4,7 @@ PROJECT(TDengine)
 IF (DEFINED VERNUMBER)
   SET(TD_VER_NUMBER ${VERNUMBER})
 ELSE ()
-  SET(TD_VER_NUMBER "2.1.5.0")
+  SET(TD_VER_NUMBER "2.0.20.10")
 ENDIF ()
 
 IF (DEFINED VERCOMPATIBLE)
diff --git a/packaging/tools/install.sh b/packaging/tools/install.sh
index 57467e4b72e4dd1ae962de922d905f1c95c5e29f..a9c3a085db9184ea59f951eaa382119778cbe65b 100755
--- a/packaging/tools/install.sh
+++ b/packaging/tools/install.sh
@@ -777,7 +777,7 @@ function is_version_compatible() {
     if [ -f ${script_dir}/driver/vercomp.txt ]; then
         min_compatible_version=`cat ${script_dir}/driver/vercomp.txt`
     else
-        min_compatible_version=$(${script_dir}/bin/tqd -V | head -1 | cut -d ' ' -f 5)
+        min_compatible_version=$(${script_dir}/bin/taosd -V | head -1 | cut -d ' ' -f 5)
     fi
 
     vercomp $curr_version $min_compatible_version
diff --git a/packaging/tools/install_power.sh b/packaging/tools/install_power.sh
index d0220cca2597ec42cd61a5775017fdbdde55b753..05eb09d8f3a8b5237c36714e964530b877e332de 100755
--- a/packaging/tools/install_power.sh
+++ b/packaging/tools/install_power.sh
@@ -746,7 +746,7 @@ function is_version_compatible() {
     if [ -f ${script_dir}/driver/vercomp.txt ]; then
         min_compatible_version=`cat ${script_dir}/driver/vercomp.txt`
     else
-        min_compatible_version=$(${script_dir}/bin/tqd -V | head -1 | cut -d ' ' -f 5)
+        min_compatible_version=$(${script_dir}/bin/powerd -V | head -1 | cut -d ' ' -f 5)
     fi
 
     vercomp $curr_version $min_compatible_version
diff --git a/snap/snapcraft.yaml b/snap/snapcraft.yaml
index aef706311d5b2dda657eec064cfd96c9a91ab30b..b06864fe5d5bbb918d3f2890aa03b487849e70f8 100644
--- a/snap/snapcraft.yaml
+++ b/snap/snapcraft.yaml
@@ -1,6 +1,6 @@
 name: tdengine
 base: core18
-version: '2.1.5.0'
+version: '2.0.20.10'
 icon: snap/gui/t-dengine.svg
 summary: an open-source big data platform designed and optimized for IoT. 
 description: |
@@ -72,7 +72,7 @@ parts:
       - usr/bin/taosd
       - usr/bin/taos
       - usr/bin/taosdemo
-      - usr/lib/libtaos.so.2.1.5.0
+      - usr/lib/libtaos.so.2.0.20.10
       - usr/lib/libtaos.so.1
       - usr/lib/libtaos.so
 
diff --git a/src/client/src/tscUtil.c b/src/client/src/tscUtil.c
index 1c610b67a56440a7d99ae698366fbbf5f5db6488..1ca9a53caa69b76f145a8466cf1d18ab5190e223 100644
--- a/src/client/src/tscUtil.c
+++ b/src/client/src/tscUtil.c
@@ -3192,6 +3192,7 @@ static void freeQueryInfoImpl(SQueryInfo* pQueryInfo) {
   pQueryInfo->tsBuf = tsBufDestroy(pQueryInfo->tsBuf);
 
   tfree(pQueryInfo->fillVal);
+  pQueryInfo->fillType = 0;
   tfree(pQueryInfo->buf);
 
   taosArrayDestroy(pQueryInfo->pUpstream);
diff --git a/src/common/src/tglobal.c b/src/common/src/tglobal.c
index 34ccfbc3fe5c5279fd668663546c8064181daa13..a58303e9fc98a0dab30da1440c32cf03c5b1fa1e 100644
--- a/src/common/src/tglobal.c
+++ b/src/common/src/tglobal.c
@@ -38,7 +38,7 @@ uint16_t tsDnodeDnodePort = 6035;  // udp/tcp
 uint16_t tsSyncPort = 6040;
 uint16_t tsArbitratorPort = 6042;
 int32_t  tsStatusInterval = 1;  // second
-int32_t  tsNumOfMnodes = 3;
+int32_t  tsNumOfMnodes = 1;
 int8_t   tsEnableVnodeBak = 1;
 int8_t   tsEnableTelemetryReporting = 1;
 int8_t   tsArbOnline = 0;
diff --git a/src/inc/taos.h b/src/inc/taos.h
index ba53c1ca8f57632d4270213be8eb7a7dbecd4dd2..6fa30737e71e8f40cee817386ad4d2c26661777f 100644
--- a/src/inc/taos.h
+++ b/src/inc/taos.h
@@ -110,19 +110,18 @@ typedef struct TAOS_MULTI_BIND {
   int            num;
 } TAOS_MULTI_BIND;
 
-
-
 DLL_EXPORT TAOS_STMT *taos_stmt_init(TAOS *taos);
 DLL_EXPORT int        taos_stmt_prepare(TAOS_STMT *stmt, const char *sql, unsigned long length);
 DLL_EXPORT int        taos_stmt_set_tbname_tags(TAOS_STMT* stmt, const char* name, TAOS_BIND* tags);
 DLL_EXPORT int        taos_stmt_set_tbname(TAOS_STMT* stmt, const char* name);
 DLL_EXPORT int        taos_stmt_set_sub_tbname(TAOS_STMT* stmt, const char* name);
+
 DLL_EXPORT int        taos_stmt_is_insert(TAOS_STMT *stmt, int *insert);
 DLL_EXPORT int        taos_stmt_num_params(TAOS_STMT *stmt, int *nums);
-int        taos_stmt_get_param(TAOS_STMT *stmt, int idx, int *type, int *bytes);
+DLL_EXPORT int        taos_stmt_get_param(TAOS_STMT *stmt, int idx, int *type, int *bytes);
 DLL_EXPORT int        taos_stmt_bind_param(TAOS_STMT *stmt, TAOS_BIND *bind);
-int        taos_stmt_bind_param_batch(TAOS_STMT* stmt, TAOS_MULTI_BIND* bind);
-int        taos_stmt_bind_single_param_batch(TAOS_STMT* stmt, TAOS_MULTI_BIND* bind, int colIdx);
+DLL_EXPORT int        taos_stmt_bind_param_batch(TAOS_STMT* stmt, TAOS_MULTI_BIND* bind);
+DLL_EXPORT int        taos_stmt_bind_single_param_batch(TAOS_STMT* stmt, TAOS_MULTI_BIND* bind, int colIdx);
 DLL_EXPORT int        taos_stmt_add_batch(TAOS_STMT *stmt);
 DLL_EXPORT int        taos_stmt_execute(TAOS_STMT *stmt);
 DLL_EXPORT TAOS_RES * taos_stmt_use_result(TAOS_STMT *stmt);
@@ -141,7 +140,6 @@ DLL_EXPORT int taos_select_db(TAOS *taos, const char *db);
 DLL_EXPORT int taos_print_row(char *str, TAOS_ROW row, TAOS_FIELD *fields, int num_fields);
 DLL_EXPORT void taos_stop_query(TAOS_RES *res);
 DLL_EXPORT bool taos_is_null(TAOS_RES *res, int32_t row, int32_t col);
-
 DLL_EXPORT int taos_fetch_block(TAOS_RES *res, TAOS_ROW *rows);
 DLL_EXPORT int taos_validate_sql(TAOS *taos, const char *sql);
 
diff --git a/src/inc/tcq.h b/src/inc/tcq.h
index 27c043f960c2b77609b59f2188bfa0fa67c4b3b1..7338cccfeee184e7f6834e41064e0c71fe5145a0 100644
--- a/src/inc/tcq.h
+++ b/src/inc/tcq.h
@@ -27,7 +27,7 @@ typedef struct {
   int32_t  vgId;
   char     user[TSDB_USER_LEN];
   char     pass[TSDB_KEY_LEN];
-  char     db[TSDB_ACCT_ID_LEN + TSDB_DB_NAME_LEN];
+  char     db[TSDB_ACCT_ID_LEN + TSDB_DB_NAME_LEN]; // size must same with SVnodeObj.db[TSDB_ACCT_ID_LEN + TSDB_DB_NAME_LEN]
   FCqWrite cqWrite;
 } SCqCfg;
 
diff --git a/src/kit/taosdemo/taosdemo.c b/src/kit/taosdemo/taosdemo.c
index 32bad230cfdb8d0439ebd45ac4f973b6cac88238..30687e9e101ea866ece6d34c63cc4b1ebf3807ee 100644
--- a/src/kit/taosdemo/taosdemo.c
+++ b/src/kit/taosdemo/taosdemo.c
@@ -75,7 +75,6 @@ extern char configDir[];
 #define BUFFER_SIZE         TSDB_MAX_ALLOWED_SQL_LEN
 #define COND_BUF_LEN        (BUFFER_SIZE - 30)
 #define COL_BUFFER_LEN      ((TSDB_COL_NAME_LEN + 15) * TSDB_MAX_COLUMNS)
-
 #define MAX_USERNAME_SIZE  64
 #define MAX_PASSWORD_SIZE  64
 #define MAX_HOSTNAME_SIZE  253      // https://man7.org/linux/man-pages/man7/hostname.7.html
diff --git a/src/kit/taosdump/taosdump.c b/src/kit/taosdump/taosdump.c
index 7b2102321685409ec0a9b7cbe8a6667bd6250b81..dc36dbf6714b0f3de31e40dfc1bcebaeb2c61223 100644
--- a/src/kit/taosdump/taosdump.c
+++ b/src/kit/taosdump/taosdump.c
@@ -1264,7 +1264,7 @@ static int taosGetTableDes(
                     fields[TSDB_DESCRIBE_METRIC_FIELD_INDEX].bytes + 1));
         tstrncpy(tableDes->cols[count].type,
                 (char *)row[TSDB_DESCRIBE_METRIC_TYPE_INDEX],
-                min(16, fields[TSDB_DESCRIBE_METRIC_TYPE_INDEX].bytes) + 1);
+                min(16, fields[TSDB_DESCRIBE_METRIC_TYPE_INDEX].bytes + 1));
         tableDes->cols[count].length =
             *((int *)row[TSDB_DESCRIBE_METRIC_LENGTH_INDEX]);
         tstrncpy(tableDes->cols[count].note,
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 04d6ec41264067ceda46c50770ddc34da1d198b3..cf2c66ab8c1ba201f73c7f52e44b98f11d397a54 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -5555,6 +5555,8 @@ static SSDataBlock* doIntervalAgg(void* param, bool* newgroup) {
       break;
     }
 
+    setTagValue(pOperator, pRuntimeEnv->current->pTable, pIntervalInfo->pCtx, pOperator->numOfOutput);
+
     // the pDataBlock are always the same one, no need to call this again
     setInputDataBlock(pOperator, pIntervalInfo->pCtx, pBlock, pQueryAttr->order.order);
     hashIntervalAgg(pOperator, &pIntervalInfo->resultRowInfo, pBlock, 0);
diff --git a/src/query/src/qExtbuffer.c b/src/query/src/qExtbuffer.c
index 1fe2819ea2347f8e092a3955f6d4c3269e148294..cc47cc824bcf59f0839bc5a439d4d15b89e030ea 100644
--- a/src/query/src/qExtbuffer.c
+++ b/src/query/src/qExtbuffer.c
@@ -391,11 +391,18 @@ int32_t columnValueAscendingComparator(char *f1, char *f2, int32_t type, int32_t
 
     };
     case TSDB_DATA_TYPE_NCHAR: { // todo handle the var string compare
-      int32_t ret = tasoUcs4Compare(f1, f2, bytes);
-      if (ret == 0) {
-        return 0;
+      int32_t len1 = varDataLen(f1);
+      int32_t len2 = varDataLen(f2);
+
+      if (len1 != len2) {
+        return len1 > len2 ? 1 : -1;
+      } else {
+        int32_t ret = tasoUcs4Compare(varDataVal(f1), varDataVal(f2), len1);
+        if (ret == 0) {
+          return 0;
+        }
+        return (ret < 0) ? -1 : 1;
       }
-      return (ret < 0) ? -1 : 1;
     };
     case TSDB_DATA_TYPE_UTINYINT:  DEFAULT_COMP(GET_UINT8_VAL(f1), GET_UINT8_VAL(f2));
     case TSDB_DATA_TYPE_USMALLINT: DEFAULT_COMP(GET_UINT16_VAL(f1), GET_UINT16_VAL(f2));
diff --git a/src/sync/inc/syncTcp.h b/src/sync/inc/syncTcp.h
index b322c3440c4eeb5b53b1d55a2446030b4f892e0b..e2e5234d3996608a6ed9ce952fcb08aabca7e8b5 100644
--- a/src/sync/inc/syncTcp.h
+++ b/src/sync/inc/syncTcp.h
@@ -25,7 +25,7 @@ typedef struct {
   uint32_t  serverIp;
   int16_t   port;
   int32_t   bufferSize;
-  void    (*processBrokenLink)(int64_t handleId);
+  void    (*processBrokenLink)(int64_t handleId, int32_t closedByApp);
   int32_t (*processIncomingMsg)(int64_t handleId, void *buffer);
   void    (*processIncomingConn)(SOCKET fd, uint32_t ip);
 } SPoolInfo;
diff --git a/src/sync/src/syncArbitrator.c b/src/sync/src/syncArbitrator.c
index fdbef4c9f827d77bdc1ce1874dc2b368a7467ca1..08ebe7ae3e14dade398c793e3489508e21b58f20 100644
--- a/src/sync/src/syncArbitrator.c
+++ b/src/sync/src/syncArbitrator.c
@@ -30,7 +30,7 @@
 extern void    syncProcessTestMsg(SSyncMsg *pMsg, SOCKET connFd);
 static void    arbSignalHandler(int32_t signum, void *sigInfo, void *context);
 static void    arbProcessIncommingConnection(SOCKET connFd, uint32_t sourceIp);
-static void    arbProcessBrokenLink(int64_t rid);
+static void    arbProcessBrokenLink(int64_t rid, int32_t closedByApp);
 static int32_t arbProcessPeerMsg(int64_t rid, void *buffer);
 static tsem_t  tsArbSem;
 static void *  tsArbTcpPool;
@@ -147,10 +147,10 @@ static void arbProcessIncommingConnection(SOCKET connFd, uint32_t sourceIp) {
   return;
 }
 
-static void arbProcessBrokenLink(int64_t rid) {
+static void arbProcessBrokenLink(int64_t rid, int32_t closedByApp) {
   SNodeConn *pNode = (SNodeConn *)rid;
 
-  sDebug("%s, TCP link is broken since %s, close connection", pNode->id, strerror(errno));
+  sDebug("%s, TCP link is broken since %s, closedByApp:%d", pNode->id, strerror(errno), closedByApp);
   tfree(pNode);
 }
 
diff --git a/src/sync/src/syncMain.c b/src/sync/src/syncMain.c
index e9b24315d095c3a379f9702079f7c93be5149282..68bafb09ca82a7a55b8eb3cd94c24138f5ef3a6c 100644
--- a/src/sync/src/syncMain.c
+++ b/src/sync/src/syncMain.c
@@ -43,7 +43,7 @@ static void    syncProcessSyncRequest(char *pMsg, SSyncPeer *pPeer);
 static void    syncRecoverFromMaster(SSyncPeer *pPeer);
 static void    syncCheckPeerConnection(void *param, void *tmrId);
 static int32_t syncSendPeersStatusMsgToPeer(SSyncPeer *pPeer, char ack, int8_t type, uint16_t tranId);
-static void    syncProcessBrokenLink(int64_t rid);
+static void    syncProcessBrokenLink(int64_t rid, int32_t closedByApp);
 static int32_t syncProcessPeerMsg(int64_t rid, void *buffer);
 static void    syncProcessIncommingConnection(SOCKET connFd, uint32_t sourceIp);
 static void    syncRemovePeer(SSyncPeer *pPeer);
@@ -1308,7 +1308,7 @@ static void syncProcessIncommingConnection(SOCKET connFd, uint32_t sourceIp) {
   pthread_mutex_unlock(&pNode->mutex);
 }
 
-static void syncProcessBrokenLink(int64_t rid) {
+static void syncProcessBrokenLink(int64_t rid, int32_t closedByApp) {
   SSyncPeer *pPeer = syncAcquirePeer(rid);
   if (pPeer == NULL) return;
 
@@ -1316,9 +1316,10 @@ static void syncProcessBrokenLink(int64_t rid) {
 
   pthread_mutex_lock(&pNode->mutex);
 
-  sDebug("%s, TCP link is broken since %s, pfd:%d sfd:%d", pPeer->id, strerror(errno), pPeer->peerFd, pPeer->syncFd);
+  sDebug("%s, TCP link is broken since %s, pfd:%d sfd:%d closedByApp:%d",
+         pPeer->id, strerror(errno), pPeer->peerFd, pPeer->syncFd, closedByApp);
   pPeer->peerFd = -1;
-  if (pPeer->isArb) {
+  if (!closedByApp && pPeer->isArb) {
     tsArbOnline = 0;
   }
 
diff --git a/src/sync/src/syncTcp.c b/src/sync/src/syncTcp.c
index 698245f9e408281e2a7c41da2d6228a1ec12217d..ccb0a67e5ca99441a1c3026fee498c36795518c5 100644
--- a/src/sync/src/syncTcp.c
+++ b/src/sync/src/syncTcp.c
@@ -177,7 +177,7 @@ static void taosProcessBrokenLink(SConnObj *pConn) {
   SPoolInfo * pInfo = &pPool->info;
 
   if (pConn->closedByApp == 0) shutdown(pConn->fd, SHUT_WR);
-  (*pInfo->processBrokenLink)(pConn->handleId);
+  (*pInfo->processBrokenLink)(pConn->handleId, pConn->closedByApp);
 
   pThread->numOfFds--;
   epoll_ctl(pThread->pollFd, EPOLL_CTL_DEL, pConn->fd, NULL);
diff --git a/src/vnode/src/vnodeMgmt.c b/src/vnode/src/vnodeMgmt.c
index e14b5a385e3e0e8a3405b3a1dcdd830ef5f10126..67b9ce5ad91c2e378c0d67080e9be5c02df81129 100644
--- a/src/vnode/src/vnodeMgmt.c
+++ b/src/vnode/src/vnodeMgmt.c
@@ -110,7 +110,9 @@ void vnodeRelease(void *vparam) {
   if (vparam == NULL) return;
 
   int32_t refCount = atomic_sub_fetch_32(&pVnode->refCount, 1);
-  vTrace("vgId:%d, release vnode, refCount:%d pVnode:%p", pVnode->vgId, refCount, pVnode);
+  int32_t vgId = pVnode->vgId;
+
+  vTrace("vgId:%d, release vnode, refCount:%d pVnode:%p", vgId, refCount, pVnode);
   assert(refCount >= 0);
 
   if (refCount > 0) {
@@ -118,10 +120,10 @@ void vnodeRelease(void *vparam) {
       tsem_post(&pVnode->sem);
     }
   } else {
-    vDebug("vgId:%d, vnode will be destroyed, refCount:%d pVnode:%p", pVnode->vgId, refCount, pVnode);
+    vDebug("vgId:%d, vnode will be destroyed, refCount:%d pVnode:%p", vgId, refCount, pVnode);
     vnodeDestroyInMWorker(pVnode);
     int32_t count = taosHashGetSize(tsVnodesHash);
-    vDebug("vgId:%d, vnode is destroyed, vnodes:%d", pVnode->vgId, count);
+    vDebug("vgId:%d, vnode is destroyed, vnodes:%d", vgId, count);
   }
 }
 
diff --git a/tests/pytest/fulltest.sh b/tests/pytest/fulltest.sh
index 06bd8d7e734c928d3fa2e9fbe70c24af7c9d967c..b86e96d0bb40c43c7f39da9b372389caa4969c4e 100755
--- a/tests/pytest/fulltest.sh
+++ b/tests/pytest/fulltest.sh
@@ -244,6 +244,7 @@ python3 ./test.py -f query/queryStddevWithGroupby.py
 python3 ./test.py -f query/querySecondtscolumnTowherenow.py
 python3 ./test.py -f query/queryFilterTswithDateUnit.py
 python3 ./test.py -f query/queryTscomputWithNow.py
+python3 ./test.py -f query/queryStableJoin.py
 python3 ./test.py -f query/computeErrorinWhere.py
 python3 ./test.py -f query/queryTsisNull.py
 python3 ./test.py -f query/subqueryFilter.py
diff --git a/tests/pytest/query/queryInterval.py b/tests/pytest/query/queryInterval.py
index d61e8cf288c97fc869f19cba6bd3d181dc60797c..129d3adc92255cfd8bb20f4622b23b2141824f88 100644
--- a/tests/pytest/query/queryInterval.py
+++ b/tests/pytest/query/queryInterval.py
@@ -73,6 +73,52 @@ class TDTestCase:
         tdSql.checkData(6, 0, "2020-09-16 00:00:00")
         tdSql.checkData(6, 1, 222.0)
 
+        # test case for https://jira.taosdata.com:18080/browse/TD-5338
+        tdSql.query("select loc,max(voltage) from st  interval(1m);")
+        tdSql.checkRows(8)
+        tdSql.checkData(0, 0, "2020-07-01 04:24:00.000")
+        tdSql.checkData(0, 1, "beijing")
+        tdSql.checkData(0, 2, 220)
+        tdSql.checkData(1, 0, "2020-07-12 18:11:00.000")
+        tdSql.checkData(1, 1, "beijing")
+        tdSql.checkData(1, 2, 221)
+        tdSql.checkData(2, 0, "2020-07-24 07:58:00.000")
+        tdSql.checkData(2, 1, "beijing")
+        tdSql.checkData(2, 2, 225)
+        tdSql.checkData(3, 0, "2020-08-04 21:44:00.000")
+        tdSql.checkData(2, 1, "beijing")
+        tdSql.checkData(3, 2, 228)
+        tdSql.checkData(4, 0, "2020-08-16 11:31:00.000")
+        tdSql.checkData(4, 1, "shanghai")
+        tdSql.checkData(4, 2, 225)
+        tdSql.checkData(5, 0, "2020-08-28 01:18:00.000")
+        tdSql.checkData(5, 1, "shanghai")
+        tdSql.checkData(5, 2, 228)
+        tdSql.checkData(6, 0, "2020-09-08 15:04:00.000")
+        tdSql.checkData(6, 1, "beijing")
+        tdSql.checkData(6, 2, 222)
+        tdSql.checkData(7, 0, "2020-09-20 04:51:00.000")
+        tdSql.checkData(7, 1, "shanghai")
+        tdSql.checkData(7, 2, 222)
+        tdSql.query("select loc,max(voltage) from t0  interval(1m);")
+        tdSql.checkRows(5)
+        tdSql.checkData(0, 0, "2020-07-01 04:24:00.000")
+        tdSql.checkData(0, 1, "beijing")
+        tdSql.checkData(0, 2, 220)
+        tdSql.checkData(1, 0, "2020-07-12 18:11:00.000")
+        tdSql.checkData(1, 1, "beijing")
+        tdSql.checkData(1, 2, 221)
+        tdSql.checkData(2, 0, "2020-07-24 07:58:00.000")
+        tdSql.checkData(2, 1, "beijing")
+        tdSql.checkData(2, 2, 225)
+        tdSql.checkData(3, 0, "2020-08-04 21:44:00.000")
+        tdSql.checkData(2, 1, "beijing")
+        tdSql.checkData(3, 2, 228)       
+        tdSql.checkData(4, 0, "2020-09-08 15:04:00.000")
+        tdSql.checkData(4, 1, "beijing")
+        tdSql.checkData(4, 2, 222)
+    
+
         # test case for https://jira.taosdata.com:18080/browse/TD-2298
         tdSql.execute("create database test keep 36500")
         tdSql.execute("use test")
diff --git a/tests/pytest/query/queryStableJoin.py b/tests/pytest/query/queryStableJoin.py
new file mode 100644
index 0000000000000000000000000000000000000000..825942bad8f867301281ffab46f1b7df20fa23f6
--- /dev/null
+++ b/tests/pytest/query/queryStableJoin.py
@@ -0,0 +1,300 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import tdLog
+from util.cases import tdCases
+from util.sql import tdSql
+import random
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor(), logSql)
+
+        self.ts = 1600000000000
+        self.num = 10
+
+    def run(self):
+        tdSql.prepare()        
+        # test case for https://jira.taosdata.com:18080/browse/TD-5206
+        
+        tdSql.execute('''create stable stable_1
+                    (ts timestamp , q_int int , q_bigint bigint , q_smallint smallint , q_tinyint tinyint, 
+                    q_bool bool , q_binary binary(20) , q_nchar nchar(20) ,q_float float , q_double double , q_ts timestamp) 
+                    tags(loc nchar(20) , t_int int , t_bigint bigint , t_smallint smallint , t_tinyint tinyint, 
+                    t_bool bool , t_binary binary(20) , t_nchar nchar(20) ,t_float float , t_double double );''')
+        tdSql.execute('''create stable stable_2
+                    (ts timestamp , q_int int , q_bigint bigint , q_smallint smallint , q_tinyint tinyint, 
+                    q_bool bool , q_binary binary(20) , q_nchar nchar(20) ,q_float float , q_double double , q_ts timestamp) 
+                    tags(loc nchar(20) , t_int int , t_bigint bigint , t_smallint smallint , t_tinyint tinyint, 
+                    t_bool bool , t_binary binary(20) , t_nchar nchar(20) ,t_float float , t_double double );''')
+        tdSql.execute('''create table table_0 using stable_1 
+                    tags('table_0' , '0' , '0' , '0' , '0' , 0 , '0' , '0' , '0' , '0' )''')
+        tdSql.execute('''create table table_1 using stable_1 
+                    tags('table_1' , '2147483647' , '9223372036854775807' , '32767' , '127' , 1 , 
+                    'binary1' , 'nchar1' , '1' , '11' )''')
+        tdSql.execute('''create table table_2 using stable_1 
+                    tags('table_2' , '-2147483647' , '-9223372036854775807' , '-32767' , '-127' , false , 
+                    'binary2' , 'nchar2nchar2' , '-2.2' , '-22.22')''')
+        tdSql.execute('''create table table_3 using stable_1 
+                    tags('table_3' , '3' , '3' , '3' , '3' , true , 'binary3' , 'nchar3' , '33.33' , '3333.3333' )''')
+        tdSql.execute('''create table table_4 using stable_1 
+                    tags('table_4' , '4' , '4' , '4' , '4' , false , 'binary4' , 'nchar4' , '-444.444' , '-444444.444444' )''')
+        tdSql.execute('''create table table_5 using stable_1 
+                    tags('table_5' , '5' , '5' , '5' , '5' , true , 'binary5' , 'nchar5' , '5555.5555' , '55555555.55555555' )''')
+        tdSql.execute('''create table table_21 using stable_2 
+                    tags('table_5' , '5' , '5' , '5' , '5' , true , 'binary5' , 'nchar5' , '5555.5555' , '55555555.55555555' )''')
+
+        for i in range(self.num):        
+            tdSql.execute('''insert into table_0 values(%d, %d, %d, %d, %d, 0, 'binary.%s', 'nchar.%s', %f, %f, %d)''' 
+                            % (self.ts + i, i, i, i, i, i, i, i, i, self.ts + i))
+            tdSql.execute('''insert into table_1 values(%d, %d, %d, %d, %d, 1, 'binary1.%s', 'nchar1.%s', %f, %f, %d)''' 
+                            % (self.ts + i, 2147483647-i, 9223372036854775807-i, 32767-i, 127-i, 
+                            i, i, random.random(), random.random(), 1262304000001 + i))
+            tdSql.execute('''insert into table_2 values(%d, %d, %d, %d, %d, true, 'binary2.%s', 'nchar2nchar2.%s', %f, %f, %d)''' 
+                            % (self.ts + i, -2147483647+i, -9223372036854775807+i, -32767+i, -127+i, 
+                            i, i, random.uniform(-1,0), random.uniform(-1,0), 1577836800001 + i))
+            tdSql.execute('''insert into table_3 values(%d, %d, %d, %d, %d, false, 'binary3.%s', 'nchar3.%s', %f, %f, %d)''' 
+                            % (self.ts + i, random.randint(-2147483647, 2147483647), 
+                            random.randint(-9223372036854775807, 9223372036854775807), random.randint(-32767, 32767),
+                            random.randint(-127, 127), random.randint(-100, 100), random.randint(-10000, 10000), 
+                            random.uniform(-100000,100000), random.uniform(-1000000000,1000000000), self.ts + i))
+            tdSql.execute('''insert into table_4 values(%d, %d, %d, %d, %d, true, 'binary4.%s', 'nchar4.%s', %f, %f, %d)''' 
+                            % (self.ts + i, i, i, i, i, i, i, i, i, self.ts + i))
+            tdSql.execute('''insert into table_5 values(%d, %d, %d, %d, %d, false, 'binary5.%s', 'nchar5.%s', %f, %f, %d)''' 
+                            % (self.ts + i, i, i, i, i, i, i, i, i, self.ts + i))  
+            tdSql.execute('''insert into table_21 values(%d, %d, %d, %d, %d, false, 'binary5.%s', 'nchar5.%s', %f, %f, %d)''' 
+                            % (self.ts + i, i, i, i, i, i, i, i, i, self.ts + i)) 
+            
+
+        tdLog.info("==========TEST1:test all table data==========")
+        sql = '''select * from stable_1,stable_2  where stable_1.t_nchar = stable_2.t_nchar and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_tinyint  = stable_2.t_tinyint  and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_binary = stable_2.t_binary and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_double = stable_2.t_double and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_smallint = stable_2.t_smallint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bigint = stable_2.t_bigint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_int = stable_2.t_int and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_float = stable_2.t_float and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bool = stable_2.t_bool and stable_1.ts = stable_2.ts;'''
+        tdSql.error(sql)
+        
+        tdLog.info("==========TEST1:test drop table_0 data==========")
+        sql = '''drop table table_0;'''
+        tdSql.execute(sql)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_nchar = stable_2.t_nchar and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_tinyint  = stable_2.t_tinyint  and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_binary = stable_2.t_binary and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_double = stable_2.t_double and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_smallint = stable_2.t_smallint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bigint = stable_2.t_bigint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_int = stable_2.t_int and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_float = stable_2.t_float and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bool = stable_2.t_bool and stable_1.ts = stable_2.ts;'''
+        tdSql.error(sql)
+
+        tdLog.info("==========TEST1:test drop table_1 data==========")
+        sql = '''drop table table_1;'''
+        tdSql.execute(sql)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_nchar = stable_2.t_nchar and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_tinyint  = stable_2.t_tinyint  and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_binary = stable_2.t_binary and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_double = stable_2.t_double and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_smallint = stable_2.t_smallint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bigint = stable_2.t_bigint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_int = stable_2.t_int and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_float = stable_2.t_float and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bool = stable_2.t_bool and stable_1.ts = stable_2.ts;'''
+        tdSql.error(sql)
+
+        tdLog.info("==========TEST1:test drop table_2 data==========")
+        sql = '''drop table table_2;'''
+        tdSql.execute(sql)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_nchar = stable_2.t_nchar and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_tinyint  = stable_2.t_tinyint  and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_binary = stable_2.t_binary and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_double = stable_2.t_double and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_smallint = stable_2.t_smallint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bigint = stable_2.t_bigint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_int = stable_2.t_int and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_float = stable_2.t_float and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bool = stable_2.t_bool and stable_1.ts = stable_2.ts;'''
+        tdSql.error(sql)
+
+        tdLog.info("==========TEST1:test drop table_3 data==========")
+        sql = '''drop table table_3;'''
+        tdSql.execute(sql)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_nchar = stable_2.t_nchar and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_tinyint  = stable_2.t_tinyint  and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_binary = stable_2.t_binary and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_double = stable_2.t_double and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_smallint = stable_2.t_smallint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bigint = stable_2.t_bigint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_int = stable_2.t_int and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_float = stable_2.t_float and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bool = stable_2.t_bool and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+
+        tdLog.info("==========TEST1:test drop table_4 data==========")
+        sql = '''drop table table_4;'''
+        tdSql.execute(sql)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_nchar = stable_2.t_nchar and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_tinyint  = stable_2.t_tinyint  and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_binary = stable_2.t_binary and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_double = stable_2.t_double and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_smallint = stable_2.t_smallint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bigint = stable_2.t_bigint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_int = stable_2.t_int and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_float = stable_2.t_float and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bool = stable_2.t_bool and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(self.num)
+
+        tdLog.info("==========TEST1:test drop table_5 data==========")
+        sql = '''drop table table_5;'''
+        tdSql.execute(sql)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_nchar = stable_2.t_nchar and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(0)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_tinyint  = stable_2.t_tinyint  and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(0)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_binary = stable_2.t_binary and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(0)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_double = stable_2.t_double and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(0)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_smallint = stable_2.t_smallint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(0)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bigint = stable_2.t_bigint and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(0)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_int = stable_2.t_int and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(0)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_float = stable_2.t_float and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(0)
+        sql = '''select * from stable_1,stable_2  where stable_1.t_bool = stable_2.t_bool and stable_1.ts = stable_2.ts;'''
+        tdSql.query(sql)
+        tdSql.checkRows(0)
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
\ No newline at end of file
diff --git a/tests/pytest/tools/taosdemoAllTest/TD-4985/query-limit-offset.py b/tests/pytest/tools/taosdemoAllTest/TD-4985/query-limit-offset.py
index 4edef88cf182eee88e42615fb007bbe4756f0c7c..7f551bcefd152007ebab7a1bc7d110468b69115a 100644
--- a/tests/pytest/tools/taosdemoAllTest/TD-4985/query-limit-offset.py
+++ b/tests/pytest/tools/taosdemoAllTest/TD-4985/query-limit-offset.py
@@ -176,12 +176,8 @@ class TDTestCase:
         tdSql.checkData(0, 1, 5)
         tdSql.checkData(1, 1, 6)
         tdSql.checkData(2, 1, 7)
-
-
         os.system("rm -rf tools/taosdemoAllTest/TD-4985/query-limit-offset.py.sql")
 
-
-
     def stop(self):
         tdSql.close()
         tdLog.success("%s successfully executed" % __file__)
diff --git a/tests/pytest/tools/taosdemoAllTest/taosdemoTestInsertWithJson.py b/tests/pytest/tools/taosdemoAllTest/taosdemoTestInsertWithJson.py
index 4d80328c289921959303e6610888b4b1a20411dc..a0b669d5f12e9ba8e2052f82c2d6d8ac349bd017 100644
--- a/tests/pytest/tools/taosdemoAllTest/taosdemoTestInsertWithJson.py
+++ b/tests/pytest/tools/taosdemoAllTest/taosdemoTestInsertWithJson.py
@@ -180,13 +180,14 @@ class TDTestCase:
         os.system("%staosdemo -f tools/taosdemoAllTest/insertColumnsAndTagNum4096.json -y " % binPath)
         tdSql.query("select count(*) from db.stb0")
         tdSql.checkData(0, 0, 10000) 
+
         tdSql.execute("drop database if exists db")
         os.system("%staosdemo -f tools/taosdemoAllTest/insertInterlaceRowsLarge1M.json -y " % binPath)
         tdSql.query("select count(*) from db.stb0")
         tdSql.checkRows(0)
-        tdSql.execute("drop database if exists db") 
+        tdSql.execute("drop database if exists db")
         os.system("%staosdemo -f tools/taosdemoAllTest/insertColumnsNum0.json -y " % binPath)
-        tdSql.execute("use db") 
+        tdSql.execute("use db")
         tdSql.query("show stables like 'stb0%' ")
         tdSql.checkData(0, 2, 11)
         tdSql.execute("drop database if exists db") 
@@ -196,7 +197,7 @@ class TDTestCase:
         os.system("%staosdemo -f tools/taosdemoAllTest/insertBinaryLenLarge16374AllcolLar49151.json -y " % binPath)   
         tdSql.query("select count(*) from db.stb0") 
         tdSql.checkRows(1)
-        tdSql.query("select count(*) from db.stb1") 
+        tdSql.query("select count(*) from db.stb1")
         tdSql.checkRows(1)
         tdSql.error("select * from db.stb4")
         tdSql.error("select * from db.stb2")
@@ -221,7 +222,7 @@ class TDTestCase:
         tdSql.checkData(0, 0, "2020-03-31 12:00:00.000")
         tdSql.query("select first(ts) from blf.p_0_topics_2")
         tdSql.checkData(0, 0, "2019-10-01 00:00:00")
-        tdSql.query("select last(ts) from blf.p_0_topics_6 ")        
+        tdSql.query("select last(ts) from blf.p_0_topics_6 ")
         tdSql.checkData(0, 0, "2020-09-29 23:59:00")
         os.system("%staosdemo -f tools/taosdemoAllTest/insertMaxNumPerReq.json -y " % binPath)
         tdSql.execute("use db")
@@ -324,6 +325,7 @@ class TDTestCase:
         
         
         
+
     def stop(self):
         tdSql.close()
         tdLog.success("%s successfully executed" % __file__)
diff --git a/tests/pytest/tools/taosdemoTestTblAlt.py b/tests/pytest/tools/taosdemoTestTblAlt.py
index 56c535916a51046e65b2ddd9813141ddb8848bd1..b70525ae4d87465a59ad524067d8b1e4a61d526a 100644
--- a/tests/pytest/tools/taosdemoTestTblAlt.py
+++ b/tests/pytest/tools/taosdemoTestTblAlt.py
@@ -98,8 +98,8 @@ class TDTestCase:
                     break
                 time.sleep(1)
 
-            print("alter table test.meters add column col10 int")
-            tdSql.execute("alter table test.meters add column col10 int")
+            print("alter table test.meters add column c10 int")
+            tdSql.execute("alter table test.meters add column c10 int")
             print("insert into test.t9 values (now, 1, 2, 3, 4, 0)")
             tdSql.execute("insert into test.t9 values (now, 1, 2, 3, 4, 0)")
 
diff --git a/tests/tsim/src/simExe.c b/tests/tsim/src/simExe.c
index a05f46ce0de54628f289c937e959ccc3337e00a9..397accfea57fec92dbe2b7f9b5c4b730a91e9cbd 100644
--- a/tests/tsim/src/simExe.c
+++ b/tests/tsim/src/simExe.c
@@ -808,6 +808,11 @@ bool simExecuteNativeSqlCommand(SScript *script, char *rest, bool isSlow) {
               break;
             case TSDB_DATA_TYPE_BINARY:
             case TSDB_DATA_TYPE_NCHAR:
+              if (length[i] < 0 || length[i] > 1 << 20) {
+                fprintf(stderr, "Invalid length(%d) of BINARY or NCHAR\n", length[i]);
+                exit(-1);
+              }
+
               memset(value, 0, MAX_QUERY_VALUE_LEN);
               memcpy(value, row[i], length[i]);
               value[length[i]] = 0;