Question

I created classes Rankings and DateFilter.

Each rankings class has a DateFilter class that should produce the cutoff date. I am trying to be able to create a filter so that everything created after that date will be displayed in a table.

However, the comparison does not work. Can you see a problem?

Here is my DateFilter class:

<?php

include ("Filter.php");

class DateFilter extends Filter
{
    //@param daysOld: how many days can be passed to be included in filter
    //Ex. If daysOld = 7, everything that is less than a week old is included
    private $interval;

    public function DateFilter($daysOld)
    {
        $this->interval = new DateInterval('P'.$daysOld.'D');
    }

    //@Return: Returns a DateTime that is the earliest possible date to be included in the filter
    function createLimitDate()
    {
        $now = new DateTime();
        return $now->sub($this->interval);
    }

    //generates SQL code for checking date
    //Ex. WHERE limitDate > created... if > means before
    function genSQL()
    {
        $limitDate = $this->createLimitDate();

        return $limitDate->format('Y-m-d') . " < 'created'";
    }
}
?>

And my Rankings Class:

<?php

class Rankings 
{
    private $filter;

    //@params: $filty is the filter given to these rankings
    public function Rankings($filty)
    {
        $this->filter = $filty;
    }

    //@return: returns the html code for the rankings
    public function display()
    {
        echo '<table border="1" align="center">'.
                    '<tr align="center" style="font-weight:bold;">
                        <b><td>#</td><td>NAME</td><td>Date</td></b>
                    </tr>
                    ';

            //hardcoding DB
            $where = $this->filter->genSQL();

            $qry = mysql_query("SELECT * FROM  `pix` 
                                WHERE $where
                                ");
                if (!$qry)
                    die("FAIL: " . mysql_error());

            $i = 1;
            while($row = mysql_fetch_array($qry))
            {
                $name = $row['uniquename'];
                $created = $row['created'];
                echo ' <tr>
                            <td>'. $i . '</td>'.
                            '<td>' . $name . '</td>'.
                            '<td>'. $created . '</td>'.
                        '</tr>';

                $i += 1;
            }

            echo '</table>';
            echo $where;
    }
}
?>

I’m calling it like this:

$test = new DateFilter(100);

$rankings = new Rankings($test);
$rankings->display();

In that example, nothing is displayed, even though I’m sure everything in my datebase was uploaded less than 100 days ago.

Answer 1

Throw in some quotes around the date you’re passing to MySQL, and drop the quotes around your column name:

return "'" . $limitDate->format('Y-m-d') . "' < created";