MYSQLI_TRANS_START_READ_WRITE预版本MySQL 5.6

Question

$conn->begin_transaction(MYSQLI_TRANS_START_READ_WRITE); wont work because XAMPP doesn't have MySQL 5.6, and I can't figure out for the life of me how to get a new version working. Is there a way to have this read/write transaction pre-5.6? Leaving it blank or putting in MYSQLI_TRANS_START_WITH_CONSISTENT_SNAPSHOT seems to not make any inserts/updates work.

PHP function it's any help:

function vote($accid, $postid, $votedir) {
    include $_SERVER['DOCUMENT_ROOT'].'/database.php';
    $conn = new mysqli($sqlservername, $sqlusername, $sqlpassword, $sqldbname);
    $conn->begin_transaction();

    $stmt = $conn->prepare('SELECT vote FROM votes WHERE accid = ? AND postid = ?');
    $stmt->bind_param('ss', $accid, $postid);
    $stmt->execute();
    $result = $stmt->get_result();

    $updateStmt = null;
    if ($result->num_rows == 0) {
        $updateStmt = $conn->prepare('INSERT INTO votes (accid, postid, vote) VALUES (?, ?, ?)');
        $updateStmt->bind_param('ssi', $accid, $postid, $votedir);
    } else {
        $existingVote = $result->fetch_assoc()['vote'];
        $updateStmt = $conn->prepare('UPDATE votes SET vote = ? WHERE accid = ? AND postid = ?');
        if ($existingVote == $votedir) {
            // They're undoing their existing vote
            $updateStmt->bind_param('iss', 0, $accid, $postid);
        } else {
            // They haven't voted before
            $updateStmt->bind_param('iss', $votedir, $accid, $postid);
        }

    }
    $conn->commit();
}