将线串转换为点数组？

我有PostGIS的Postgres的，我需要线串转换为点将线串转换为点数组？

我已与此answer检查的阵列，我的问题是相似的，但也是我需要从这个

聚集到阵列

Linestring((3.584731 60.739211,3.590472 60.738030,3.592740 60.736220))

这个

["3.584731 60.739211","3.590472 60.738030","3.592740 60.736220"]

我该怎么办呢？

来源

2016-04-27 Bergutov Ruslan

你试过了什么？ –

我有选择'WITH rstemp如（SELECT st_dumppoints（st_astext（路径））AS路径，ID FROM route_sequence） SELECT rcc.order， rcc.checkpoint_id， rcc.route_id， rcc.is_forward， ARRAY_AGG（ST_X （rstemp.path.geom）） FROM route_cached_checkpoint AS RCC JOIN route_sequence AS RS ON rs.id = ANY（rcc.next_rsq） JOIN rstemp ON rstemp.id = rs.id WHERE rcc.date =（DATE“2016 -04-27'）;' –

我建议你[创建一个函数]（http://www.postgresql.org/docs/9.5/static/sql-createfunction.html）来做到这一点。 –

好了，我不知道你为什么会需要这一点，但在这里你去：

WITH 
    route_sequence AS (
     SELECT id, path 
     FROM (
     VALUES 
      (1, 'Linestring(3.584731 60.739211,3.590472 60.738030,3.592740 60.736220)'), 
      (2, 'Linestring(3.584731 60.739211,3.590472 60.738030,3.592740 60.736220)') 
    ) AS route_sequence(id, path) 
), 
    rstemp AS (
     SELECT 
     route_sequence.id, 
     array_agg(
      ST_X(points.geom)::CHARACTER VARYING 
      || ' ' 
      || ST_Y(points.geom)::CHARACTER VARYING 
      ORDER BY points.path[1] ASC 
     ) AS coordinates 
     FROM route_sequence, ST_DumpPoints(path) as points(path, geom) 
     GROUP BY route_sequence.id 
) 
SELECT * 
FROM rstemp 
;

我很好奇，想知道你为什么会在这里需要一个数组。也许有另一种方式。你为什么不能保留由ST_DumpPoints生成的初始geom？

来源

2016-04-28 17:50:32

昨天在午夜我已经创建选择，我需要，无论如何感谢您的答案（我会尝试一下，也许它会工作得更快）为什么我需要数组？这将被序列化为json python for api，从这个json两个移动应用程序（ios和android）将在地图上创建多义线，所以这就是它我现在将发布我的示例 P.S.对不起，我的英语 –

好吧，那有道理:) –

WITH points_text AS (SELECT 
        (st_dumppoints(path)).geom AS points, 
        (st_dumppoints(path)).path AS points_path, 
        rs.id, 
        rcc.checkpoint_id, 
        rcc.route_id, 
        rcc."order", 
        rcc.is_forward, 
        rcc.is_primary 
       FROM route_cacheed_checkpoint AS rcc 
        JOIN route_sequence AS rs ON rs.id = ANY (rcc.next_rsq) 
       WHERE rcc.date = (DATE '2016-04-28') AND rcc.is_primary = TRUE) 
SELECT 
    array_agg(to_char(ST_X(points), 'FM99.9999990') || to_char(ST_Y(points), '99.9999990') ORDER BY points_path) AS path, 
    pt.checkpoint_id, 
    pt.route_id, 
    pt."order", 
    pt.is_forward     AS is_forward_direction, 
    pt.is_primary 
FROM points_text AS pt 
GROUP BY pt.id, pt.checkpoint_id, pt.route_id, pt."order", pt.is_forward, pt.is_primary 
ORDER BY pt.is_forward DESC, pt."order";

来源

2016-04-29 04:36:15

将线串转换为点数组？

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