pgr_articulationPoints  pgRouting Manual (3.4)
pgr_articulationPoints
pgr_articulationPoints
 Return the articulation points of an undirected
graph.
Availability

Version 3.0.0

Return columns change:
seq
is removed 
Official function


Version 2.5.0

New experimental function

Description
Those vertices that belong to more than one biconnected component are called articulation points or, equivalently, cut vertices. Articulation points are vertices whose removal would increase the number of connected components in the graph. This implementation can only be used with an undirected graph.
The main characteristics are:

Works for undirected graphs.

The returned values are ordered:

node
ascending


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

The articulation points of the graph
SELECT * FROM pgr_articulationPoints(
'SELECT id, source, target, cost, reverse_cost FROM edges'
);
node

3
6
7
8
(4 rows)
Nodes in red are the articulation points.
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
(node)
Column 
Type 
Description 



Identifier of the vertex. 
See Also

The queries use the Sample Data network.

wikipedia: Biconnected component
Indices and tables