pgr_biconnectedComponents  pgRouting Manual (3.4)
pgr_biconnectedComponents
pgr_biconnectedComponents
 Biconnected components of an undirected graph.
Availability

Version 3.0.0

Return columns change:

n_seq
is removed 
seq
changed type toBIGINT


Official function


Version 2.5.0

New experimental function

Description
The biconnected components of an undirected graph are the maximal subsets of vertices such that the removal of a vertex from particular component will not disconnect the component. Unlike connected components, vertices may belong to multiple biconnected components. Vertices can be present in multiple biconnected components, but each edge can only be contained in a single biconnected component.
The main characteristics are:

Works for undirected graphs.

Components are described by edges.

The returned values are ordered:

component
ascending. 
edge
ascending.


Running time: \(O(V + E)\)
Signatures
 Example :

The biconnected components of the graph
SELECT * FROM pgr_biconnectedComponents(
'SELECT id, source, target, cost, reverse_cost FROM edges'
);
seq component edge
++
1 1 1
2 2 2
3 2 3
4 2 4
5 2 5
6 2 8
7 2 9
8 2 10
9 2 11
10 2 12
11 2 13
12 2 15
13 2 16
14 6 6
15 7 7
16 14 14
17 17 17
18 18 18
(18 rows)
Parameters
Parameter 
Type 
Description 


Edges SQL as described below. 
Inner Queries
Edges SQL
Column 
Type 
Default 
Description 


ANYINTEGER 
Identifier of the edge. 


ANYINTEGER 
Identifier of the first end point vertex of the edge. 


ANYINTEGER 
Identifier of the second end point vertex of the edge. 


ANYNUMERICAL 
Weight of the edge (



ANYNUMERICAL 
1 
Weight of the edge (

Where:
 ANYINTEGER :

SMALLINT
,INTEGER
,BIGINT
 ANYNUMERICAL :

SMALLINT
,INTEGER
,BIGINT
,REAL
,FLOAT
Result Columns
Returns set of
(seq,
component,
edge)
Column 
Type 
Description 



Sequential value starting from 1 . 


Component identifier.



Identifier of the edge that belongs to the

See Also

The queries use the Sample Data network.

Boost: Biconnected components

wikipedia: Biconnected component
Indices and tables