Components - Family of functions¶
pgr_connectedComponents - Connected components of an undirected graph.
pgr_strongComponents - Strongly connected components of a directed graph.
pgr_biconnectedComponents - Biconnected components of an undirected graph.
pgr_articulationPoints - Articulation points of an undirected graph.
pgr_bridges - Bridges of an undirected graph.
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Parameters¶
Parameter |
Type |
Default |
Description |
---|---|---|---|
Edges SQL |
|
Inner query as described below. |
Inner query¶
- Edges SQL
an SQL query which should return a set of rows with the following columns:
Column |
Type |
Default |
Description |
---|---|---|---|
id |
|
Identifier of the edge. |
|
source |
|
Identifier of the first end point vertex of the edge. |
|
target |
|
Identifier of the second end point vertex of the edge. |
|
cost |
|
Weight of the edge (source, target)
|
|
reverse_cost |
|
-1 |
Weight of the edge (target, source),
|
Where:
- ANY-INTEGER
SMALLINT, INTEGER, BIGINT
- ANY-NUMERICAL
SMALLINT, INTEGER, BIGINT, REAL, FLOAT
Result Columns¶
pgr_connectedComponents & pgr_strongComponents¶
Returns set of (seq, component, node)
Column |
Type |
Description |
---|---|---|
seq |
|
Sequential value starting from 1. |
component |
|
Component identifier. It is equal to the minimum node identifier in the component. |
node |
|
Identifier of the vertex that belongs to component. |
pgr_biconnectedComponents¶
Returns set of (seq, component, edge)
Column |
Type |
Description |
---|---|---|
seq |
|
Sequential value starting from 1. |
component |
|
Component identifier. It is equal to the minimum edge identifier in the component. |
edge |
|
Identifier of the edge. |
pgr_articulationPoints¶
Returns set of (node)
Column |
Type |
Description |
---|---|---|
node |
|
Identifier of the vertex. |
pgr_bridges¶
Returns set of (edge)
Column |
Type |
Description |
---|---|---|
edge |
|
Identifier of the edge that is a bridge. |