Question

I want to use prepared statement to insert and update data in mysqli,

Below is my database class,

class database extends mysqli
{
    ...

    # insert and update data
    public function query_stmt($sql,$types = null,$params = null)
    {
        # create a prepared statement
        $stmt = parent::prepare($sql);

        if($stmt)
        {
            # bind parameters dynamically for markers
            if($types&&$params)
            {
                $bind_names[] = $types;
                for ($i=0; $i<count($params);$i++) 
                {
                    $bind_name = 'bind' . $i;
                    $$bind_name = $params[$i];
                    $bind_names[] = &$$bind_name;
                }
                $return = call_user_func_array(array($stmt,'bind_param'),$bind_names);
            }

            # execute query 
            $result = $stmt->execute();

            if($result) return 'success!';
                else return 'failed!';

            # close statement
            $stmt->close();

        }

        else
        {
            return self::get_error();
        }
    }

    # display error
    public function get_error() 
    {
        if($this->errno || $this->error)
        {
            return sprintf("Error (%d): %s",$this->errno,$this->error);
        }
    }

    public function __destruct()
    {
        parent::close();
        //echo "Destructor Called";
    }
}

It works fine when I have a correct query like this,

$sql = "
    INSERT root_countries_cities_towns (
        tcc_names,
        cny_numberic,
        tcc_created
    )VALUES(
        ?,
        ?,
        NOW()
    )";

$mysqli->query_stmt($sql, 'ss',array('UK','004'));

But I want it to return something when I have an incorrect query, such as,

$sql = "
        INSERT root_countries_cities_townx (
            tcc_names,
            cny_numberic,
            tcc_created
        )VALUES(
            ?,
            ?,
            NOW()
        )";

the table of root_countries_cities_townx does not exist. So I want the the method of query_stmt to return this type of error message to my browser. But my method doesn’t! Why?

I have tried to test it to return some default words whether it is ok or not, but nothing at all comes out on my browser,

# execute query 
$result = $stmt->execute();

if($result) return 'success!';
else return 'failed!';

What should I add or change in the code so that it can return a positive message when it is ok and returns negative message when it is not ok?

Thanks.

Answer 1

You’re returning the error messages, not echoing them. You’d either have to modify the DB class to use echo instead of return, or do

$ret_text = $mysqli->query_stmt(...);
echo $ret_text;