mysql query points within polygon - no results

Question

I'm pretty sure that I'm doing multiple things wrong here but I'm not sure what...

The table (minus a few fields):

CREATE TABLE IF NOT EXISTS `stuff` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `lat` decimal(12,7) NOT NULL,
  `lon` decimal(12,7) NOT NULL,
  `location` point NOT NULL,  
  UNIQUE KEY `id` (`id`),
  KEY `distance` (`distance`),
  KEY `lat` (`lat`),
  KEY `lon` (`lon`),
  SPATIAL KEY `location` (`location`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=5;

The triggers to automatically set the location point:

DROP TRIGGER IF EXISTS `stuff_insert_defaults`;
DELIMITER //
CREATE TRIGGER `stuff_insert_defaults` BEFORE INSERT ON `stuff`
 FOR EACH ROW SET NEW.location = PointFromText(CONCAT('POINT(',NEW.lat,' ',NEW.lon,')'))
//
DELIMITER ;

DROP TRIGGER IF EXISTS `stuff_update_location`;
DELIMITER //
CREATE TRIGGER `stuff_update_location` BEFORE UPDATE ON `stuff`
 FOR EACH ROW SET NEW.location = PointFromText(CONCAT('POINT(',NEW.lat,' ',NEW.lon,')'))
//
DELIMITER ;

Some sample data (4 random points within the state of Colorado):

/* 4 random points within the state of colorado */
INSERT INTO `stuff` (`id`, `distance`, `lat`, `lon`, `location`) VALUES
(1, 5.0000000, 40.2488450, -103.8003460, 0x000000000101000000f6622827da1f444001df6dde38f359c0),
(2, 5.0000000, 38.4849180, -107.8726700, 0x000000000101000000f19e03cb113e4340d28c45d3d9f75ac0),
(3, 5.0000000, 39.5040250, -105.3584800, 0x000000000101000000e6ae25e483c0434049111956f1565ac0),
(4, 5.0000000, 39.1904180, -106.8179680, 0x000000000101000000ed48f59d5f9843402b4b749659b45ac0);

The rough outter boundary of the state of Colorado:

NW corner: 41.000497 -109.050149 
NE corner: 41.002380 -102.051881 
SE corner: 36.993237 -102.041959 
SW corner: 36.999037 -109.045220 

The query which SHOULD return the 4 records we inserted:

SELECT *, AsText(location) FROM stuff 
 WHERE Contains(
 GeomFromText('POLYGON((41.000497 -109.050149, 41.002380 -102.051881, 36.993237 -102.041959, 36.999037 -109.045220, 41.000497 -109.050149))'), location );

What I'm getting back...

nada... 
zip... 
nil... 
nothing...

Answer 1

As documented under Class Polygon (emphasis added):

Polygon Assertions

• The boundary of a Polygon consists of a set of LinearRing objects (that is, LineString objects that are both simple and closed ) that make up its exterior and interior boundaries.

You must therefore close the polygon by finishing at the starting point:

SELECT *, AsText(location) FROM stuff 
 WHERE Contains(
 GeomFromText('POLYGON((41.000497 -109.050149, 41.002380 -102.051881, 36.993237 -102.041959, 36.999037 -109.045220, 41.000497 -109.050149))'), location );

See it on sqlfiddle .