diff --git a/include/client/taos.h b/include/client/taos.h
index a529cf8d15..7d82b258f3 100644
--- a/include/client/taos.h
+++ b/include/client/taos.h
@@ -65,22 +65,14 @@ typedef enum {
 } TSDB_OPTION;
 
 typedef enum {
-  TSDB_OPTION_CONNECTION_CLEAR = -1,     // clear all option in this connection
+  TSDB_OPTION_CONNECTION_CLEAR = -1,     // means clear all option in this connection
   TSDB_OPTION_CONNECTION_CHARSET,        // charset, Same as the scope supported by the system
   TSDB_OPTION_CONNECTION_TIMEZONE,       // timezone, Same as the scope supported by the system
   TSDB_OPTION_CONNECTION_USER_IP,        // user ip
-  TSDB_OPTION_CONNECTION_USER_APP,       // user app
+  TSDB_OPTION_CONNECTION_USER_APP,       // user app, max lengthe is 23, truncated if longer than 23
   TSDB_MAX_OPTIONS_CONNECTION
 } TSDB_OPTION_CONNECTION;
 
-typedef enum {
-  TSDB_OPTION_CONNECT_CHARSET,
-  TSDB_OPTION_CONNECT_TIMEZONE,
-  TSDB_OPTION_CONNECT_IP,
-  TSDB_OPTION_CONNECT_APP_NAME,
-  TSDB_MAX_CONNECT_OPTIONS
-} TSDB_OPTION_CONNECT;
-
 typedef enum {
   TSDB_SML_UNKNOWN_PROTOCOL = 0,
   TSDB_SML_LINE_PROTOCOL = 1,
@@ -189,9 +181,26 @@ typedef struct TAOS_STMT_OPTIONS {
   bool    singleTableBindOnce;
 } TAOS_STMT_OPTIONS;
 
+
+/*
+ description:
+    taos_options_connection use to set extra connect options and affect behavior for a connection.
+    This function may be called multiple times to set several options.
+    Call taos_options_connection() after taos_connect() or taos_connect_auth().
+    The option argument is the option that you want to set; the arg argument is the value for the option.
+    If you want to reset the option, set arg to NULL.
+ input:
+    taos:   returned by taos_connect
+    option: option name
+    arg:    option value(string)
+ output:
+    0:      success
+    others: fail, error msg can be got by taos_errstr(NULL)
+*/
+DLL_EXPORT int        taos_options_connection(TAOS *taos, TSDB_OPTION_CONNECTION option, const void *arg, ...);
+
 DLL_EXPORT void       taos_cleanup(void);
 DLL_EXPORT int        taos_options(TSDB_OPTION option, const void *arg, ...);
-DLL_EXPORT int        taos_options_connection(TAOS *taos, TSDB_OPTION_CONNECTION option, const void *arg, ...);
 DLL_EXPORT setConfRet taos_set_config(const char *config);
 DLL_EXPORT int        taos_init(void);
 DLL_EXPORT TAOS      *taos_connect(const char *ip, const char *user, const char *pass, const char *db, uint16_t port);
diff --git a/include/common/tmsg.h b/include/common/tmsg.h
index 9af98898a6..626df01032 100644
--- a/include/common/tmsg.h
+++ b/include/common/tmsg.h
@@ -3420,7 +3420,6 @@ typedef struct {
   SAppHbReq         app;
   SQueryHbReqBasic* query;
   SHashObj*         info;  // hash<Skv.key, Skv>
-  char              name[TSDB_APP_NAME_LEN];
   char              userApp[TSDB_APP_NAME_LEN];
   uint32_t          userIp;
 } SClientHbReq;
diff --git a/include/util/tencode.h b/include/util/tencode.h
index b66e79fa60..efe3883d16 100644
--- a/include/util/tencode.h
+++ b/include/util/tencode.h
@@ -413,7 +413,9 @@ static FORCE_INLINE int32_t tDecodeBinary(SDecoder* pCoder, uint8_t** val, uint3
 
 static FORCE_INLINE int32_t tDecodeCStrAndLen(SDecoder* pCoder, char** val, uint32_t* len) {
   TAOS_CHECK_RETURN(tDecodeBinary(pCoder, (uint8_t**)val, len));
-  (*len) -= 1;
+  if (*len > 0) {
+    (*len) -= 1;
+  }
   return 0;
 }
 
@@ -427,7 +429,10 @@ static int32_t tDecodeCStrTo(SDecoder* pCoder, char* val) {
   uint32_t len;
   TAOS_CHECK_RETURN(tDecodeCStrAndLen(pCoder, &pStr, &len));
 
-  TAOS_MEMCPY(val, pStr, len + 1);
+  if (pCoder->pos + 1 < pCoder->size) {
+    TAOS_MEMCPY(val, pStr, len + 1);
+  }
+
   return 0;
 }
 
diff --git a/source/client/src/clientMain.c b/source/client/src/clientMain.c
index ca9bd4b2ee..65edf4058d 100644
--- a/source/client/src/clientMain.c
+++ b/source/client/src/clientMain.c
@@ -76,7 +76,6 @@ static timezone_t setConnnectionTz(const char* val){
   if (pTimezoneMap == NULL){
     pTimezoneMap = taosHashInit(0, MurmurHash3_32, false, HASH_ENTRY_LOCK);
     if (pTimezoneMap == NULL) {
-      atomic_store_32(&lock_c, 0);
       goto END;
     }
     taosHashSetFreeFp(pTimezoneMap, freeTz);
@@ -85,7 +84,6 @@ static timezone_t setConnnectionTz(const char* val){
   if (pTimezoneNameMap == NULL){
     pTimezoneNameMap = taosHashInit(0, taosIntHash_64, false, HASH_ENTRY_LOCK);
     if (pTimezoneNameMap == NULL) {
-      atomic_store_32(&lock_c, 0);
       goto END;
     }
   }
diff --git a/source/client/test/connectOptionsTest.cpp b/source/client/test/connectOptionsTest.cpp
index 95129b5aac..bf4e402f28 100644
--- a/source/client/test/connectOptionsTest.cpp
+++ b/source/client/test/connectOptionsTest.cpp
@@ -474,6 +474,8 @@ TEST(charsetCase, alter_charset_Test) {
 
   execQueryFail(pConn, "alter dnode 1 'charset gbk'");
   execQueryFail(pConn, "local 'charset gbk'");
+
+  taos_close(pConn);
 }
 
 #ifndef WINDOWS
@@ -493,6 +495,8 @@ TEST(timezoneCase, alter_timezone_Test) {
   check_timezone(pConn, "show local variables", "Asia/Shanghai");
 
   execQueryFail(pConn, "alter dnode 1 'timezone Asia/Kolkata'");
+
+  taos_close(pConn);
 }
 
 char *tz_test[] = {
diff --git a/source/libs/scalar/src/sclfunc.c b/source/libs/scalar/src/sclfunc.c
index 3fac8d2718..1da9a8f123 100644
--- a/source/libs/scalar/src/sclfunc.c
+++ b/source/libs/scalar/src/sclfunc.c
@@ -584,7 +584,7 @@ static bool isCharStart(char c) {
 static int32_t trimHelper(char *orgStr, char* remStr, int32_t orgLen, int32_t remLen, bool trimLeft, bool isNchar) {
   if (trimLeft) {
     int32_t pos = 0;
-    for (int32_t i = 0; i < orgLen; i += remLen) {
+    for (int32_t i = 0; i < orgLen - remLen; i += remLen) {
       if (memcmp(orgStr + i, remStr, remLen) == 0) {
         if (isCharStart(orgStr[i + remLen]) || isNchar) {
           pos = i + remLen;