Deduce a value's type from a stringified version of that value

deduce-type.php

// Deduce Type
// James Futhey, 2015
//
// Useful for parsing a $_GET or $_POST value and knowing it's MySQL-compatible type 

function deduceType ($value) {
	if (strlen(strval($value)) === 0) {
		return "null";
	}
	if ($value === "true" || $value === "false") {
		return "boolean";
	}
	
	$type = "text";
	if (is_numeric($value)) {
		// We either have an int or float (decimal)
		$type = "int";
		
		if (!ctype_digit(strval($value))) {
			$type = "decimal";
			return $type;
		}
	} else {
		// We either have a varchar, text, or datestring
		if (strlen($value) < 256) {
			$type = "varchar";
		}
		
		try {
		    if (new DateTime($value) !== FALSE) {
			  $type = "timestamp";
			  return $type;
			}
		} catch (Exception $e) {
			return $type;
		}
	}
	return $type;
}

If you need to use this for anything other than SQL, you should return "float" instead of "decimal", and return "string" instead of "text" or "varchar".