PDO/PHP - Check if row exist

Solution:

You can just check the return value directly.

{-code-1}
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If you are asking about checking without fetching then simply have MySQL return a1 (or use theCOUNT() command).

$sql = 'SELECT 1 from table WHERE id = ? LIMIT 1';
//$sql = 'SELECT COUNT(*) from table WHERE param = ?'; // for checking >1 records
$stmt = $conn->prepare($sql);
$stmt->bindParam(1, $_GET['id'], PDO::PARAM_INT);
$stmt->execute();

if($stmt->fetchColumn()) echo 'found';
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Solution:

if($stmt->rowCount() == 0) 
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should work fine, since the number of rows can't be less than zero in any event at all.

From the manual:

For most databases,PDOStatement::rowCount() does not return the number of rows affected by aSELECT statement. Instead, usePDO::query() to issue aSELECT COUNT(*) statement with the same predicates as your intendedSELECT statement, then usePDOStatement::fetchColumn() to retrieve the number of rows that will be returned. Your application can then perform the correct action.

I would suggest reading up on that here.

Solution:

Heres what I use in my object classes:

function exists_by_id () {
    // check if object exists by id
    $stm = DB::$pdo->prepare('select count(*) from `table` where `column`=:column');
    $stm->bindParam(':column', $this->column);
    $stm->execute();
    $res = $stm->fetchColumn();

    if ($res > 0) {
        return true;
    }
    else {
        return false;
    }
}
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