摘要: 1、ST_Accum 构造几何图形数组。该函数支持3d、圆、曲面、多面体、三角网、TIN数据。geometry[]ST_Accum(geometry set geomfield);示例SQL:SELECT (ST_Accum(the_geom)) As all_em, ST_AsText((ST_Accum(the_geom))[1]) As grabone,(ST_Accum(the_geom))[2:4] as grab_rest FROM (SELECT ST_MakePoint(a*CAST(random()*10 As integer), a*CAST(random()*10 As 阅读全文
posted @ 2013-03-12 23:52 清灵阁主 阅读(2155) 评论(0) 推荐(0)
摘要: 1、&&A && B: 当二维A范围覆盖二维B范围时,返回真。boolean &&( geometry A , geometry B );boolean &&( geography A , geography B ); 注意事项:这个操作将会利用任何可用的索引的几何图形,2.0.0版本支持多面体、圆形、曲线。实例:SELECT tbl1.column1, tbl2.column1, tbl1.column2 && tbl2.column2 AS overlapsFROM ( VALUES(1, 'LINES 阅读全文
posted @ 2013-03-12 00:05 清灵阁主 阅读(1825) 评论(0) 推荐(0)