执行最近邻域搜索的简单方法是按与要查询的几何图形的距离对候选表进行排序，然后获取最小距离对应的表记录
SELECT streets.gid, streets.name
FROM
nyc_streets streets,
nyc_subway_stations subways
WHERE subways.name = ‘Broad St‘
ORDER BY ST_Distance(streets.geom, subways.geom) ASC
LIMIT 1;
原文：https://www.cnblogs.com/yjh1995/p/13893384.html