Working with past 2 months (date)

Question

I'm trying to delete the past 2 months in my database.

I'm saving things in my database like this format date("nY"); zo the output would be 8-2013

Now i'm trying to delete the past 2 months like this:

Code:

echo "<h2>Opruimen.</h2>";

$AFGELOPENMAAND = date("n-Y",strtotime("-1 Months"));
$AFGELOPENMAAND2 = date("n-Y",strtotime("-2 Months"));

$result = $pdo->prepare("SELECT * FROM photos WHERE geupload = $AFGELOPENMAAND OR geupload = $AFGELOPENMAAND2");
$result->execute();
$hoeveel = $result->rowCount();

if($hoeveel != 0){
    foreach($result as $row){
        unlink($row["thumb"]);
        unlink($row["location"]);

        $resultDEL = $pdo->prepare('DELETE FROM photos WHERE id = :id');
        $resultDEL->execute(array(':id' => $row["id"]));

        echo 'De vorige 2 maanden zijn verwijdert.';
        echo '<meta http-equiv="refresh" content="2; URL=admin.php">';  
    }
}else{
    echo 'Deze actie is al uitgevoerd of het is niet nodig!!';
}

But i can see with my else, if he found something or not. And it doesn't find rows in my database, but there are some with the past 2 months in it.

Am i doing something wrong with my query ?

Grz

Answer 1

您必须引用在mysql中搜索的字符串，当前正在搜索month_value-year_value，它是一个负整数

Answer 2

You have some issues...

Prepared statements don't have to be prepared for each iteration when the bound data changes:

if($hoeveel != 0){
    $resultDEL = $pdo->prepare('DELETE FROM photos WHERE id = :id'); //put it here
    foreach($result as $row){
        unlink($row["thumb"]);
        unlink($row["location"]);

        $resultDEL->execute(array(':id' => $row["id"]));

        echo 'De vorige 2 maanden zijn verwijdert.';
        echo '<meta http-equiv="refresh" content="2; URL=admin.php">';  
    }
}else{
   echo 'Deze actie is al uitgevoerd of het is niet nodig!!';
}

However You could also delete them directly:

$result = $pdo->prepare("DELETE FROM photos WHERE geupload = $AFGELOPENMAAND OR geupload = $AFGELOPENMAAND2");
$result->execute();

Rule of thumb : When you read something from DB, and have to process each line so that there is a resulting DB query, 99 out of 100 cases you could have done it entirely in the DB, saving a lot of bandwidth and time.

EDIT AdrianBR found the problem... Don't store dates as strings. DB systems are good at handling their own defined datatypes, use them.

Answer 3

Replace this:

$result = $pdo->prepare("SELECT * FROM photos WHERE geupload = $AFGELOPENMAAND OR geupload = $AFGELOPENMAAND2");
$result->execute();

with this

$result = $pdo->prepare("SELECT * FROM photos WHERE geupload = '".$AFGELOPENMAAND."' OR  geupload = '".$AFGELOPENMAAND2."'");
$result->execute();

Answer 4

My advice, change your "geupload" field to a DATETIME (or DATE) field instead of VARCHAR, it's much much easier to work with and the database can handle this field like a real date instead of a string (like mentioned before).

You can remove the rows, older then two months like this then:

DELETE FROM photos WHERE TIMESTAMPDIFF(MONTH, geupload, NOW()) > 2

You can easily insert or update the current time into this field like this:

INSERT INTO photos (.., .., geupload) VALUES (.., .., NOW())

UPDATE photos SET geupload = NOW()