PostGIS ST_Contains无法返回数据

Question

我在使用PostGIS 2.1.7和PostgreSQL 9.4时遇到了一个奇怪的情况。

我想匹配位于广东省境内的一个点（纬度：36.671112，经度：-121.662636，因为我们可以在这个地图上看到：https://www.google.com/maps/d/viewer?mid=zHggIvE-1G0A.kW1YFh5cNOJU&usp=sharing）用下面的查询：

select name 
from zones 
where ST_Contains(area, ST_SetSRID(ST_Point(-121.662636, 36.671112), 4326)) 

其中zones定义如下：

create table zones (
    name text, 
    kml text, 
    area geometry 
) 

insert into zones (name, kml) 
values (
    'California', 
    '<Polygon><outerBoundaryIs><LinearRing><coordinates>-118.603375,33.478098,0 -118.60403,33.47654,0 -118.601185,33.469853,0 -118.593969,33.467198,0 -118.575901,33.448261,0 -118.570927,33.439351,0 -118.563442,33.434381,0 -118.558715,33.433419,0 -118.53738,33.434608,0 -118.52323,33.430733,0 -118.516267,33.425075,0 -118.515914,33.422417,0 -118.503952,33.424234,0 -118.48875,33.419826,0 -118.484949,33.412131,0 -118.478465,33.38632,0 -118.482609,33.369914,0 -118.48877,33.356649,0 -118.481886,33.344123,0 -118.465368,33.326056,0 -118.456309,33.32182,0 -118.440047,33.318638,0 -118.402941,33.320901,0 -118.374768,33.320065,0 -118.360332,33.31533,0 -118.343249,33.305234,0 -118.325244,33.299075,0 -118.316787,33.301137,0 -118.305084,33.310323,0 -118.303174,33.320264,0 -118.310213,33.335795,0 -118.316083,33.342928,0 -118.32446,33.348782,0 -118.365094,33.388374,0 -118.368301,33.40711,0 -118.370323,33.409285,0 -118.382037,33.409883,0 -118.423576,33.427258,0 -118.445812,33.428907,0 -118.477646,33.448392,0 -118.48557,33.446213,0 -118.499669,33.447879,0 -118.500212,33.449592,0 -118.530702,33.468071,0 -118.54453,33.474119,0 -118.585936,33.473819,0 -118.598783,33.477939,0 -118.603375,33.478098,0 </coordinates></LinearRing></outerBoundaryIs></Polygon>' 
) 

update zones 
set area = ST_GeomFromKML(kml) 

这里所返回的内容：

name 
------ 
(0 row) 

虽然它应该返回此相反：

name 
----------- 
California 
(1 row) 

你看到什么不好的查询或表创建脚本？

（我说，这是不具优势的情况下与该点本身，因为我遇到有超过60个的不同点，相同的问题，所有的位于广东省境内）

Answer 1

它不返回因为点不在该区域内。

尝试此查询：

select st_xmax(area), st_ymax(area), st_xmin(area), st_ymin(area) from zones; 

你会看到的一点是很好的最大值和最小值外点：

"st_xmax","st_ymax","st_xmin","st_ymin" 
-118.303174,33.478098,-118.60403,33.299075 

您的区域，似乎是一个岛屿的海岸洛杉矶（这个岛上有一个叫做“阿瓦隆”的小镇），而不是整个州。你可以使用像QGIS这样的GIS来形象化你的图层 - 你很快就会看到问题，这就是我所做的！）。