diff --git a/a8/mysql.cc b/a8/mysql.cc
index 604b5a2..d605e3d 100644
--- a/a8/mysql.cc
+++ b/a8/mysql.cc
@@ -143,7 +143,8 @@ namespace a8
         int Query::ExecQuery(const char* querystr, std::vector<a8::XValue> args)
         {
             impl_->FreeLastDataSet();
-            int err = mysql_query(impl_->Conn(), FormatSql(querystr, args).c_str());
+            std::string real_sql = FormatSql(querystr, args).c_str();
+            int err = mysql_query(impl_->Conn(), real_sql.c_str());
             if(err == 0){
                 impl_->mysqlres = mysql_store_result(impl_->Conn());
                 if(RowsNum() > 0){
@@ -157,7 +158,8 @@ namespace a8
         bool Query::ExecScript(const char* scriptstr, std::vector<a8::XValue> args)
         {
             impl_->FreeLastDataSet();
-            return mysql_query(impl_->Conn(), FormatSql(scriptstr , args).c_str()) == 0;
+            std::string real_sql = FormatSql(scriptstr , args).c_str();
+            return mysql_query(impl_->Conn(), real_sql.c_str()) == 0;
         }
 
         std::string Query::FormatSqlEx(const char* fmt, std::vector<a8::XValue> args)