MySQLにアクセスして、ユニークなuserid, followerid, timestampを生成する。

generate_unique_pair.php

<?php

# usage: $ php generate_unique_pair.php 10000 > unique_pairs.txt

define('NUM_PAIRS', $argv[1]);
define('MAX_USERS', 5000 * 10000);

$dbname = 'db01';
$host = 'localhost';
$user = 'root';
$password = 'root';
$table = 't01';

$pairs = array();
$pdo = new PDO(
	'mysql:dbname=' . $dbname . ';host=' . $host . ';charset=latin1', $user, $password, array(PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION, PDO::ATTR_PERSISTENT => true)
);

while (TRUE) {
	if (count($pairs) >= NUM_PAIRS) {
		break;
	}
	$userid = rand(1, MAX_USERS);
	$followerid = rand(1, MAX_USERS);
	if (select($pdo, $table, $userid, $followerid) === FALSE) {
		$pairs[] = array($userid, $followerid);
	}
}

foreach ($pairs as $pair) {
	echo $pair[0] . "\t" . $pair[1] . "\t" . (time()+rand(-100000000, 100000000)) . "\n";
}

/* $iと$fの組み合わせが存在してればTRUE, 存在しなければFALSE */
function select($pdo, $tablename, $i, $f) {
	try {
		$stmt = $pdo->prepare("select f from " . $tablename . " where i = :i and f = :f");
		$stmt->bindValue(':i', $i, PDO::PARAM_INT);
		$stmt->bindValue(':f', $f, PDO::PARAM_INT);
		$stmt->execute();
		$row = $stmt->fetch(PDO::FETCH_ASSOC);
		if ($row === FALSE) {
			return FALSE;
		}
		return TRUE;
	} catch (PDOException $e) {
		die("ERROR. " . $e->getMessage());
	}
}