How to Reset PDO Result Array Pointer for Multiple Iterations?

PDO: Resetting Array Pointer in Results

When migrating from MySQL SELECT methods to PDO, iterating through a fetched array twice with each iteration starting from row zero poses a challenge. PDO lacks an equivalent to MySQL's mysql_data_seek() function.

Consider using the following approach:

1. Save Results to an Array:

   • Execute the PDO query and store the results in an array by calling $stmt->fetchAll().

2. Iterate Array Twice:

   • Iterate through the $rows array twice, performing the desired operations within each iteration.

Here's an example:

$pdo = new PDO('mysql:host=' . $host . ';dbname='.$database, $username, $password);
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$stmt = $pdo->prepare('SELECT * FROM mytable WHERE active = 1 ORDER BY name ASC');
$stmt->setFetchMode(PDO::FETCH_ASSOC);
$stmt->execute();

$rows = $stmt->fetchAll();

foreach ($rows as $r) {
    // first run
}

foreach ($rows as $r) {
    // second run
}

This approach effectively simulates the desired behavior of resetting the array pointer, enabling multiple iterations through the same result set.

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