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strange problems using mysql-connector and c++

Dan Feerst (85)
I have been having trouble with this code for a while. It compiles, but I throw an exception which I don't know what to make of.
About halfway down in the last function I threw in a "cout" statement to test the data being sent to the SQL server. It looks exactly right. I can use the exact command in SQL to make the change myself, but I get this when I execute the code.
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UPDATE USERS SET CREDITS='999999999' WHERE UID='1'
# ERR: SQLException in sqlcomm.cpp(pushData_USERS) on line 60
# ERR:  (MySQL error code: 0, SQLState: 00000 )
999999999


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efine DATABASE                "TEST"
#define USERNAME                "root"
#define PASSWORD                "423490769iss"
#define ADDRESS                 "tcp://127.0.0.1:3306"

#include "mysql_connection.h"
#include <cppconn/driver.h>
#include <cppconn/exception.h>
#include <cppconn/resultset.h>
#include <cppconn/statement.h>
#include <cppconn/prepared_statement.h>
#include <string>
#include <sstream>
using namespace std;


string pullData_USERS( string uid, string column ){
    try {
        sql::Driver *driver;
        sql::Connection *con;
        sql::Statement *stmt;
        sql::ResultSet *res;
        driver = get_driver_instance();
        con = driver->connect( ADDRESS,USERNAME,PASSWORD );
        con->setSchema( DATABASE );
        stmt = con->createStatement();
        ostringstream strstr;
        strstr << "SELECT "<< column <<" FROM USERS "<< " WHERE UID='" << uid << "'";
        string s = strstr.str();
        res = stmt->executeQuery(s.c_str());
        while( res->next())
			s = res->getString(column);
		return s;
        } catch (sql::SQLException &e) {
        cout << "# ERR: SQLException in " << __FILE__;
        cout << "(" << __FUNCTION__ << ") on line " << __LINE__ << endl;
        cout << "# ERR: " << e.what();
        cout << " (MySQL error code: " << e.getErrorCode();
        cout << ", SQLState: " << e.getSQLState() << " )" << endl;
        }			
    return NULL;
}

void pushData_USERS(string uid, string column, string input){
    try {
        sql::Driver *driver;
        sql::Connection *con;
        sql::Statement *stmt;
        driver = get_driver_instance();
        con = driver->connect( ADDRESS,USERNAME,PASSWORD );
        con->setSchema( DATABASE );
        stmt = con->createStatement();
        ostringstream strstr;
        strstr << "UPDATE USERS SET "<< column << "='" << input <<"' WHERE UID='" << uid<<"'";
        string s = strstr.str();
        cout <<s.c_str()<<endl;
        stmt->executeQuery(s.c_str());
        } catch (sql::SQLException &e) {
        cout << "# ERR: SQLException in " << __FILE__;
        cout << "(" << __FUNCTION__ << ") on line " << __LINE__ << endl;
        cout << "# ERR: " << e.what();
        cout << " (MySQL error code: " << e.getErrorCode();
        cout << ", SQLState: " << e.getSQLState() << " )" << endl;
        }			
}


int main(){
pushData_USERS("1","CREDITS","999999999");
string q = pullData_USERS("1","CREDITS");
cout <<q<<endl;
}


norm b (337)
Just a thought: try using execute() in lieu of executeQuery() since "update" does not produce a result set and executeQuery() expects one.
Dan Feerst (85)
That was it!!
Thanks.
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