diff --git a/storage/ctc/ctc_ddl_rewriter_plugin.cc b/storage/ctc/ctc_ddl_rewriter_plugin.cc
index e211c5af89c9566565d3e8c76afe7f7b62674185..f15dfca082f75714b8fbb622481845cb9886d32f 100644
--- a/storage/ctc/ctc_ddl_rewriter_plugin.cc
+++ b/storage/ctc/ctc_ddl_rewriter_plugin.cc
@@ -662,11 +662,6 @@ static int check_system_var(set_var_base *var, string &sql_str, MYSQL_THD thd,
       ret |= ctc_check_set_opt_rule(setvar, name_str, val_str, need_forward);
     }
   }
-  if (val_str.c_str() == nullptr) {
-    my_printf_error(ER_DISALLOWED_OPERATION, "Set the variable '%s' failed: value is invalid",
-                    MYF(0), name_str.c_str());
-    return -1;
-  }
   if (strlen(val_str.c_str()) > CTC_MAX_VAR_VALUE_LEN) {
     my_printf_error(ER_DISALLOWED_OPERATION, "Set the variable '%s' failed: value is too long",
                     MYF(0), name_str.c_str());
@@ -735,7 +730,7 @@ static int ctc_check_set_opt(string &sql_str, MYSQL_THD thd, bool &need_forward)
     ret = ctc_set_var_meta(thd, variables_info, &set_opt_request);
     if (ret != 0 && set_opt_request.err_code != 0) {
       string err_msg = set_opt_request.err_msg;
-      my_printf_error(set_opt_request.err_code, "execute set opt failed, error_message:%s", MYF(0), err_msg.c_str());
+      my_printf_error(set_opt_request.err_code, "%s", MYF(0), err_msg.c_str());
       return ret;
     }
   }
diff --git a/storage/ctc/ctc_meta_data.cc b/storage/ctc/ctc_meta_data.cc
index a76dde0ffa83bbbaac4bdf65fe5ee7557cde88fe..e61308a29b34b6991bc0dc69bb9039adb9ca64d5 100644
--- a/storage/ctc/ctc_meta_data.cc
+++ b/storage/ctc/ctc_meta_data.cc
@@ -776,7 +776,6 @@ int close_ctc_mdl_thd(uint32_t thd_id, uint32_t mysql_inst_id) {
 
 static void ctc_get_set_var_item(THD* new_thd, sys_var* sysvar, Item** res MY_ATTRIBUTE((unused)),
                                  const char* var_value, bool is_null_value, bool var_is_int) {
-  string val_str = string(var_value, strlen(var_value));
   switch (sysvar->show_type()) {
     case SHOW_INT:
     case SHOW_LONG:
@@ -795,7 +794,7 @@ static void ctc_get_set_var_item(THD* new_thd, sys_var* sysvar, Item** res MY_AT
       break;
     case SHOW_BOOL:
     case SHOW_MY_BOOL:
-      if(val_str == "1" || val_str == "0") {
+      if(strcmp(var_value, "1") == 0 || strcmp(var_value, "0") == 0) {
         *res = new (new_thd->mem_root)
           Item_int(var_value, (uint)strlen(var_value));
       } else {
@@ -967,7 +966,6 @@ int ctc_set_sys_var(ctc_set_opt_request *broadcast_req) {
   lex_end(new_thd->lex);
   new_thd->release_resources();
   delete new_thd;
-
   my_thread_end();
   
   return ret;