需要 Lat 形式的 Path，long 使用 pgrouting

Question

我正在使用此查询查找使用 postgresql、postgis、pgrouting 的路径，postgis_topology 使用 nodejs

client.query(
"WITH dijkstra AS (
  SELECT * 
  FROM pgr_dijkstra('SELECT id,source,target,distance AS cost 
     FROM edges_noded',230965,3338,false)) 
 SELECT seq, 
   CASE WHEN dijkstra.node = edges_noded.source THEN edges_noded.the_geom 
   ELSE ST_Reverse(edges_noded.the_geom) END AS route_geom 
 FROM dijkstra JOIN edges_noded ON(edge = id) 
 ORDER BY seq",(err,res)=>{ var data = res.rows;})

现在的问题是这个查询 returns 两列是

我认为上图中的 route_geom 列有路径信息。

如何修改上述查询以获取经纬度形式的路径。

我需要经纬度形式的完整路径。

Answer 1

如果我没理解错的话，您只需将现有的坐标转换为您的应用程序可以读取的格式。您可以直接从 PostGIS 获得许多格式。以下是您可能感兴趣的一些内容：

数据样本

CREATE TEMPORARY TABLE t (seq INT, the_geom GEOMETRY);
INSERT INTO t VALUES (1,'POINT(1 2)'),(2,'POINT(2 3)');

PostGIS 几何格式的几何图形 - 正如您目前所做的那样。

SELECT seq, the_geom FROM t;
 seq |                  the_geom                  
-----+--------------------------------------------
   1 | 0101000000000000000000F03F0000000000000040
   2 | 010100000000000000000000400000000000000840
(2 Zeilen)

在单独的列中检索纬度和经度数据 - ST_X, ST_Y

SELECT seq, ST_X(the_geom), ST_Y(the_geom) FROM t;
 seq | st_x | st_y 
-----+------+------
   1 |    1 |    2
   2 |    2 |    3
(2 Zeilen)

作为 WKT - ST_AsText

SELECT seq, ST_AsText(the_geom) FROM t;
 seq | st_astext  
-----+------------
   1 | POINT(1 2)
   2 | POINT(2 3)
(2 Zeilen)

.. 或 GeoJSON - ST_AsGeoJSON

SELECT seq, ST_AsGeoJSON(the_geom) FROM t;
 seq |             st_asgeojson             
-----+--------------------------------------
   1 | {"type":"Point","coordinates":[1,2]}
   2 | {"type":"Point","coordinates":[2,3]}
(2 Zeilen)

所以你的CTE很可能看起来像这样

WITH dijkstra AS (
  SELECT *
  FROM pgr_dijkstra('SELECT id,source,target,distance AS cost 
    FROM edges_noded',230965,3338,false)) 
SELECT seq, 
  CASE WHEN dijkstra.node = edges_noded.source THEN ST_X(edges_noded.the_geom)
  ELSE ST_X(ST_Reverse(edges_noded.the_geom)) END AS route_geom_x,
  CASE WHEN dijkstra.node = edges_noded.source THEN ST_Y(edges_noded.the_geom)
  ELSE ST_Y(ST_Reverse(edges_noded.the_geom)) END AS route_geom_y 
FROM dijkstra JOIN edges_noded ON(edge = id) 
ORDER BY seq

需要 Lat 形式的 Path，long 使用 pgrouting

Need Path in the form of Lat,long using pgrouting

sql

postgresql

postgis

node.js

pgrouting