$re = '/((?P<fulldate>(?P<date>(\d{4}-\d{2}-\d{2}))T(?P<time>(\d{2}:\d{2}:\d{2}(?:\.\d+)?)))(?P<tz>(Z|[\+-]\d{2}:\d{2})?))/m';
$str = 'CAST(N\'2016-01-19T15:21:32.59+02:00\'';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php