pgr_bdDijkstra

pgr_bdDijkstra — Returns the shortest path using Bidirectional Dijkstra algorithm.

_images/boost-inside.jpeg

Boost 图内部

可用性:

  • 版本3.2.0

    • 拟议 的签名:

  • 版本3.0.0

    • 官方 函数

  • 版本2.5.0

  • 版本2.4.0

    • pgr_bdDijsktra (一对一)上的签名更改

      • 不再支持旧签名

  • 版本2.0.0

描述

主要特点是:

  • 仅在具有正成本的边进行处理。

    • 成本列上的负值被解释为边不存在。

  • 当存在路径时返回值。

  • 当没有路径时:

    • 当起始顶点和结束顶点相同时。

      • 未包含值 \((v, v)\)aggregate cost\(0\)

    • 当起始顶点和结束顶点不同且不存在路径时:

      • 未包含值 \((u, v)\)aggregate cost\(\infty\)

  • 出于优化目的,起始顶点或结束顶点中的任何重复值都将被忽略。

  • 运行时间(最坏情况): \(O((V \log V + E))\)

  • 对于起始顶点和结束顶点之间存在路径的大型图:

    • 预计终止速度比 pgr_dijkstra 更快

签名

总结

pgr_bdDijkstra(Edges SQL, start vid, end vid, [directed])
pgr_bdDijkstra(Edges SQL, start vid, end vids, [directed])
pgr_bdDijkstra(Edges SQL, start vids, end vid, [directed])
pgr_bdDijkstra(Edges SQL, start vids, end vids, [directed])
pgr_bdDijkstra(Edges SQL, Combinations SQL, [directed])
返回 (seq, path_seq, [start_vid], [end_vid], node, edge, cost, agg_cost) 的集合
OR EMPTY SET

一对一

pgr_bdDijkstra(Edges SQL, start vid, end vid, [directed])
返回 (seq, path_seq, node, edge, cost, agg_cost) 的集合
OR EMPTY SET
示例:

有向 图上从顶点 \(6\) 到顶点 \(10\)

SELECT * FROM pgr_bdDijkstra(
  'select id, source, target, cost, reverse_cost from edges',
  6, 10, true);
 seq | path_seq | node | edge | cost | agg_cost
-----+----------+------+------+------+----------
   1 |        1 |    6 |    4 |    1 |        0
   2 |        2 |    7 |    8 |    1 |        1
   3 |        3 |   11 |    9 |    1 |        2
   4 |        4 |   16 |   16 |    1 |        3
   5 |        5 |   15 |    3 |    1 |        4
   6 |        6 |   10 |   -1 |    0 |        5
(6 rows)

一对多

pgr_bdDijkstra(Edges SQL, start vid, end vids, [directed])
返回 (seq, path_seq, end_vid, node, edge, cost, agg_cost) 的集合
OR EMPTY SET
示例:

有向 图上从顶点 \(6\) 到顶点 \(\{10, 17\}\)

SELECT * FROM pgr_bdDijkstra(
  'select id, source, target, cost, reverse_cost from edges',
  6, ARRAY[10, 17]);
 seq | path_seq | end_vid | node | edge | cost | agg_cost
-----+----------+---------+------+------+------+----------
   1 |        1 |      10 |    6 |    4 |    1 |        0
   2 |        2 |      10 |    7 |    8 |    1 |        1
   3 |        3 |      10 |   11 |    9 |    1 |        2
   4 |        4 |      10 |   16 |   16 |    1 |        3
   5 |        5 |      10 |   15 |    3 |    1 |        4
   6 |        6 |      10 |   10 |   -1 |    0 |        5
   7 |        1 |      17 |    6 |    4 |    1 |        0
   8 |        2 |      17 |    7 |    8 |    1 |        1
   9 |        3 |      17 |   11 |   11 |    1 |        2
  10 |        4 |      17 |   12 |   13 |    1 |        3
  11 |        5 |      17 |   17 |   -1 |    0 |        4
(11 rows)

多对一

pgr_bdDijkstra(Edges SQL, start vids, end vid, [directed])
返回 (seq, path_seq, start_vid, node, edge, cost, agg_cost) 的集合
OR EMPTY SET
示例:

有向 图上从顶点 \(\{6, 1\}\) 到顶点 \(17\)

SELECT * FROM pgr_bdDijkstra(
  'select id, source, target, cost, reverse_cost from edges',
  ARRAY[6, 1], 17);
 seq | path_seq | start_vid | node | edge | cost | agg_cost
-----+----------+-----------+------+------+------+----------
   1 |        1 |         1 |    1 |    6 |    1 |        0
   2 |        2 |         1 |    3 |    7 |    1 |        1
   3 |        3 |         1 |    7 |    8 |    1 |        2
   4 |        4 |         1 |   11 |   11 |    1 |        3
   5 |        5 |         1 |   12 |   13 |    1 |        4
   6 |        6 |         1 |   17 |   -1 |    0 |        5
   7 |        1 |         6 |    6 |    4 |    1 |        0
   8 |        2 |         6 |    7 |    8 |    1 |        1
   9 |        3 |         6 |   11 |   11 |    1 |        2
  10 |        4 |         6 |   12 |   13 |    1 |        3
  11 |        5 |         6 |   17 |   -1 |    0 |        4
(11 rows)

多对多

pgr_bdDijkstra(Edges SQL, start vids, end vids, [directed])
Returns set of (seq, path_seq, start_vid, end_vid, node, edge, cost, agg_cost)
OR EMPTY SET
示例:

无向 图上从顶点 \(\{6, 1\}\) 到顶点 \(\{10, 17\}\)

SELECT * FROM pgr_bdDijkstra(
  'select id, source, target, cost, reverse_cost from edges',
  ARRAY[6, 1], ARRAY[10, 17],
  directed => false);
 seq | path_seq | start_vid | end_vid | node | edge | cost | agg_cost
-----+----------+-----------+---------+------+------+------+----------
   1 |        1 |         1 |      10 |    1 |    6 |    1 |        0
   2 |        2 |         1 |      10 |    3 |    7 |    1 |        1
   3 |        3 |         1 |      10 |    7 |    4 |    1 |        2
   4 |        4 |         1 |      10 |    6 |    2 |    1 |        3
   5 |        5 |         1 |      10 |   10 |   -1 |    0 |        4
   6 |        1 |         1 |      17 |    1 |    6 |    1 |        0
   7 |        2 |         1 |      17 |    3 |    7 |    1 |        1
   8 |        3 |         1 |      17 |    7 |    8 |    1 |        2
   9 |        4 |         1 |      17 |   11 |   11 |    1 |        3
  10 |        5 |         1 |      17 |   12 |   13 |    1 |        4
  11 |        6 |         1 |      17 |   17 |   -1 |    0 |        5
  12 |        1 |         6 |      10 |    6 |    2 |    1 |        0
  13 |        2 |         6 |      10 |   10 |   -1 |    0 |        1
  14 |        1 |         6 |      17 |    6 |    2 |    1 |        0
  15 |        2 |         6 |      17 |   10 |    5 |    1 |        1
  16 |        3 |         6 |      17 |   11 |   11 |    1 |        2
  17 |        4 |         6 |      17 |   12 |   13 |    1 |        3
  18 |        5 |         6 |      17 |   17 |   -1 |    0 |        4
(18 rows)

组合

pgr_bdDijkstra(Edges SQL, Combinations SQL, [directed])
Returns set of (seq, path_seq, start_vid, end_vid, node, edge, cost, agg_cost)
OR EMPTY SET
示例:

无向 图上使用组合表

组合表:

SELECT source, target FROM combinations;
 source | target
--------+--------
      5 |      6
      5 |     10
      6 |      5
      6 |     15
      6 |     14
(5 rows)

查询:

SELECT * FROM pgr_bdDijkstra(
  'SELECT id, source, target, cost, reverse_cost FROM edges',
  'SELECT source, target FROM combinations',
  false);
 seq | path_seq | start_vid | end_vid | node | edge | cost | agg_cost
-----+----------+-----------+---------+------+------+------+----------
   1 |        1 |         5 |       6 |    5 |    1 |    1 |        0
   2 |        2 |         5 |       6 |    6 |   -1 |    0 |        1
   3 |        1 |         5 |      10 |    5 |    1 |    1 |        0
   4 |        2 |         5 |      10 |    6 |    2 |    1 |        1
   5 |        3 |         5 |      10 |   10 |   -1 |    0 |        2
   6 |        1 |         6 |       5 |    6 |    1 |    1 |        0
   7 |        2 |         6 |       5 |    5 |   -1 |    0 |        1
   8 |        1 |         6 |      15 |    6 |    2 |    1 |        0
   9 |        2 |         6 |      15 |   10 |    3 |    1 |        1
  10 |        3 |         6 |      15 |   15 |   -1 |    0 |        2
(10 rows)

参数

类型

描述

Edges SQL

TEXT

Edges SQL 如下所述

Combinations SQL

TEXT

Combinations SQL 如下所述

start vid

BIGINT

路径起始顶点的标识符。

start vids

ARRAY[BIGINT]

起始顶点的标识符数组。

end vid

BIGINT

路径结束顶点的标识符。

end vids

ARRAY[BIGINT]

结束顶点的标识符数组。

可选参数

类型

默认

描述

directed

BOOLEAN

true

  • true 时,该图被视为有 有向

  • 如果为 false ,则该图被视为 无向

内部查询

Edges SQL

类型

默认

描述

id

ANY-INTEGER

边的标识符。

source

ANY-INTEGER

边的第一个端点顶点的标识符。

target

ANY-INTEGER

边的第二个端点顶点的标识符。

cost

ANY-NUMERICAL

边(source, target)的权重

reverse_cost

ANY-NUMERICAL

-1

边(target, source)的权重

  • 当为负时:边( target, source )不存在,因此它不是图的一部分。

其中:

ANY-INTEGER:

SMALLINT, INTEGER, BIGINT

ANY-NUMERICAL:

SMALLINT, INTEGER, BIGINT, REAL, FLOAT

分量 SQL

参数

类型

描述

source

ANY-INTEGER

出发顶点的标识符。

target

ANY-INTEGER

到达顶点的标识符。

其中:

ANY-INTEGER:

SMALLINT, INTEGER, BIGINT

结果列

返回 (seq, path_seq [, start_vid] [, end_vid], node, edge, cost, agg_cost) 的集合

类型

描述

seq

INTEGER

1 开始的顺序值。

path_seq

INTEGER

路径中的相对位置。 路径开头的值为 1

start_vid

BIGINT

起始顶点的标识符。 当查询中有多个起始向量时返回。

end_vid

BIGINT

结束顶点的标识符。 当查询中有多个结束顶点时返回。

node

BIGINT

start_vidend_vid 路径中节点的标识符。

edge

BIGINT

用于从路径序列中的 node 到下一个节点的边的标识符。 -1 表示路径的最后一个节点。

cost

FLOAT

从使用 edgenode 遍历到路径序列中的下一个节点的成本。

agg_cost

FLOAT

start_vidnode 的总成本。

其他示例

示例1:

演示中重复的值被忽略,且结果被排序。

SELECT * FROM pgr_bdDijkstra(
  'select id, source, target, cost, reverse_cost from edges',
  ARRAY[7, 10, 15, 10, 10, 15], ARRAY[10, 7, 10, 15]);
 seq | path_seq | start_vid | end_vid | node | edge | cost | agg_cost
-----+----------+-----------+---------+------+------+------+----------
   1 |        1 |         7 |      10 |    7 |    8 |    1 |        0
   2 |        2 |         7 |      10 |   11 |    9 |    1 |        1
   3 |        3 |         7 |      10 |   16 |   16 |    1 |        2
   4 |        4 |         7 |      10 |   15 |    3 |    1 |        3
   5 |        5 |         7 |      10 |   10 |   -1 |    0 |        4
   6 |        1 |         7 |      15 |    7 |    8 |    1 |        0
   7 |        2 |         7 |      15 |   11 |    9 |    1 |        1
   8 |        3 |         7 |      15 |   16 |   16 |    1 |        2
   9 |        4 |         7 |      15 |   15 |   -1 |    0 |        3
  10 |        1 |        10 |       7 |   10 |    2 |    1 |        0
  11 |        2 |        10 |       7 |    6 |    4 |    1 |        1
  12 |        3 |        10 |       7 |    7 |   -1 |    0 |        2
  13 |        1 |        10 |      15 |   10 |    5 |    1 |        0
  14 |        2 |        10 |      15 |   11 |    9 |    1 |        1
  15 |        3 |        10 |      15 |   16 |   16 |    1 |        2
  16 |        4 |        10 |      15 |   15 |   -1 |    0 |        3
  17 |        1 |        15 |       7 |   15 |    3 |    1 |        0
  18 |        2 |        15 |       7 |   10 |    2 |    1 |        1
  19 |        3 |        15 |       7 |    6 |    4 |    1 |        2
  20 |        4 |        15 |       7 |    7 |   -1 |    0 |        3
  21 |        1 |        15 |      10 |   15 |    3 |    1 |        0
  22 |        2 |        15 |      10 |   10 |   -1 |    0 |        1
(22 rows)

示例2:

使 start vidsend vids 相同。

SELECT * FROM pgr_bdDijkstra(
  'select id, source, target, cost, reverse_cost from edges',
  ARRAY[7, 10, 15], ARRAY[7, 10, 15]);
 seq | path_seq | start_vid | end_vid | node | edge | cost | agg_cost
-----+----------+-----------+---------+------+------+------+----------
   1 |        1 |         7 |      10 |    7 |    8 |    1 |        0
   2 |        2 |         7 |      10 |   11 |    9 |    1 |        1
   3 |        3 |         7 |      10 |   16 |   16 |    1 |        2
   4 |        4 |         7 |      10 |   15 |    3 |    1 |        3
   5 |        5 |         7 |      10 |   10 |   -1 |    0 |        4
   6 |        1 |         7 |      15 |    7 |    8 |    1 |        0
   7 |        2 |         7 |      15 |   11 |    9 |    1 |        1
   8 |        3 |         7 |      15 |   16 |   16 |    1 |        2
   9 |        4 |         7 |      15 |   15 |   -1 |    0 |        3
  10 |        1 |        10 |       7 |   10 |    2 |    1 |        0
  11 |        2 |        10 |       7 |    6 |    4 |    1 |        1
  12 |        3 |        10 |       7 |    7 |   -1 |    0 |        2
  13 |        1 |        10 |      15 |   10 |    5 |    1 |        0
  14 |        2 |        10 |      15 |   11 |    9 |    1 |        1
  15 |        3 |        10 |      15 |   16 |   16 |    1 |        2
  16 |        4 |        10 |      15 |   15 |   -1 |    0 |        3
  17 |        1 |        15 |       7 |   15 |    3 |    1 |        0
  18 |        2 |        15 |       7 |   10 |    2 |    1 |        1
  19 |        3 |        15 |       7 |    6 |    4 |    1 |        2
  20 |        4 |        15 |       7 |    7 |   -1 |    0 |        3
  21 |        1 |        15 |      10 |   15 |    3 |    1 |        0
  22 |        2 |        15 |      10 |   10 |   -1 |    0 |        1
(22 rows)

示例3:

手动指定的顶点组合。

SELECT * FROM pgr_bdDijkstra(
  'SELECT id, source, target, cost, reverse_cost FROM edges',
  'SELECT * FROM (VALUES (6, 10), (6, 7), (12, 10)) AS combinations (source, target)');
 seq | path_seq | start_vid | end_vid | node | edge | cost | agg_cost
-----+----------+-----------+---------+------+------+------+----------
   1 |        1 |         6 |       7 |    6 |    4 |    1 |        0
   2 |        2 |         6 |       7 |    7 |   -1 |    0 |        1
   3 |        1 |         6 |      10 |    6 |    4 |    1 |        0
   4 |        2 |         6 |      10 |    7 |    8 |    1 |        1
   5 |        3 |         6 |      10 |   11 |    9 |    1 |        2
   6 |        4 |         6 |      10 |   16 |   16 |    1 |        3
   7 |        5 |         6 |      10 |   15 |    3 |    1 |        4
   8 |        6 |         6 |      10 |   10 |   -1 |    0 |        5
   9 |        1 |        12 |      10 |   12 |   13 |    1 |        0
  10 |        2 |        12 |      10 |   17 |   15 |    1 |        1
  11 |        3 |        12 |      10 |   16 |   16 |    1 |        2
  12 |        4 |        12 |      10 |   15 |    3 |    1 |        3
  13 |        5 |        12 |      10 |   10 |   -1 |    0 |        4
(13 rows)

另请参阅

索引和表格