SQLite c++ copy table from one database to other

{
    rc = sqlite3_exec(db, "SELECT * FROM tbl", callback, NULL, &zErrMsg);
}

int callback(void *data, int argc, char **argv, char **azColName){
   int i;
   std::stringstream ss;
   ss<<"INSERT INTO Fields VALUES("
   for(i=0; i<argc; i++){
        ss<<argv[i] ? argv[i] : 0
    if(i+1<argc)
        ss<<","
    }
    ss<<")"
    rc = sqlite3_exec(db, ss.str(), NULL, NULL, &zErr);
    if(rc){
        wxMessageBox("Error opening database: " << sqlite3_errmsg(db),"Error",wxOK);
        sqlite3_close(db);
        return 1;
    }
   return 0;
}

I'm trying to copy data from one table to another, I thought about this code, is this code fine? can it be done better? Thanks.