日付の分解

<?php
// 2010-11-01 01:02:03から20101101にしたい場合
$str  = '2010-11-01 01:02:03';
$date = substr($str, 0,4) . substr($str, 5, 2) . substr($str, 8, 2);
print($date . "\n");

// 2010-11-01 01:02:03から年月日時分秒をそれぞれ別の変数に代入する場合
list($yyyy, $mm, $dd, $hh, $mi, $ss) = array(substr($str, 0,4), substr($str, 5, 2), substr($str, 8, 2), substr($str, 11, 2), substr($str, 14, 2), substr($str, 17, 2));
print($yyyy . "\n");
print($mm . "\n");
print($dd . "\n");
print($hh . "\n");
print($mi . "\n");
print($ss . "\n");

// 20101101010203から2010-11-01 01:02:03に変換する場合
$str  = '20101101010203';
$date = vsprintf("%4d-%02d-%02d %02d:%02d:%02d", sscanf($str, "%4d%2d%2d%2d%2d%2d"));
print($date . "\n");