pgr_withPointsDD
 Returns the driving distance from a starting point.
Warning
These are proposed functions for next mayor release.
Availability: 2.2.0
Modify the graph to include points and
using Dijkstra algorithm, extracts all the nodes and points that have costs less
than or equal to the value distance
from the starting point.
The edges extracted will conform the corresponding spanning tree.
pgr_withPointsDD(edges_sql, points_sql, start_vid, distance)
pgr_withPointsDD(edges_sql, points_sql, start_vid, distance, directed, driving_side, details)
pgr_withPointsDD(edges_sql, points_sql, start_vids, distance, directed, driving_side, details, equicost)
RETURNS SET OF (seq, node, edge, cost, agg_cost)
pgr_withPointsDD(edges_sql, points_sql, start_vid, distance)
directed:=true, driving_side:='b', details:=false)
RETURNS SET OF (seq, node, edge, cost, agg_cost)
Example: 

SELECT * FROM pgr_withPointsDD(
'SELECT id, source, target, cost, reverse_cost FROM edge_table ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
1, 3.8);
seq  node  edge  cost  agg_cost
++++
1  1  1  0  0
2  1  1  0.4  0.4
3  2  1  0.6  0.6
4  5  4  0.3  1.6
5  6  8  1  2.6
6  8  7  1  2.6
7  10  10  1  2.6
8  7  6  0.3  3.6
9  9  9  1  3.6
10  11  11  1  3.6
11  13  14  1  3.6
(11 rows)
Finds the driving distance depending on the optional parameters setup.
pgr_withPointsDD(edges_sql, points_sql, start_vids, distance,
directed:=true, driving_side:='b', details:=false)
RETURNS SET OF (seq, node, edge, cost, agg_cost)
Example:  Right side driving topology 

SELECT * FROM pgr_withPointsDD(
'SELECT id, source, target, cost, reverse_cost FROM edge_table ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
1, 3.8,
driving_side := 'r',
details := true);
seq  node  edge  cost  agg_cost
++++
1  1  1  0  0
2  1  1  0.4  0.4
3  2  1  1  1.4
4  6  4  0.7  2.1
5  5  4  0.3  2.4
6  6  8  1  3.4
7  8  7  1  3.4
8  10  10  1  3.4
(8 rows)
Finds the driving distance depending on the optional parameters setup.
pgr_withPointsDD(edges_sql, points_sql, start_vids, distance,
directed:=true, driving_side:='b', details:=false, equicost:=false)
RETURNS SET OF (seq, node, edge, cost, agg_cost)
edges_sql:  an SQL query, which should return a set of rows with the following columns: 

Column  Type  Default  Description 

id  ANYINTEGER 
Identifier of the edge.  
source  ANYINTEGER 
Identifier of the first end point vertex of the edge.  
target  ANYINTEGER 
Identifier of the second end point vertex of the edge.  
cost  ANYNUMERICAL 
Weight of the edge (source, target)


reverse_cost  ANYNUMERICAL 
1  Weight of the edge (target, source),

Where:
ANYINTEGER:  SMALLINT, INTEGER, BIGINT 

ANYNUMERICAL:  SMALLINT, INTEGER, BIGINT, REAL, FLOAT 
points_sql:  an SQL query, which should return a set of rows with the following columns: 

Column  Type  Description 

pid  ANYINTEGER 
(optional) Identifier of the point.

edge_id  ANYINTEGER 
Identifier of the “closest” edge to the point. 
fraction  ANYNUMERICAL 
Value in <0,1> that indicates the relative postition from the first end point of the edge. 
side  CHAR 
(optional) Value in [‘b’, ‘r’, ‘l’, NULL] indicating if the point is:

Where:
ANYINTEGER:  smallint, int, bigint 

ANYNUMERICAL:  smallint, int, bigint, real, float 
Parameter  Type  Description 

edges_sql  TEXT 
Edges SQL query as described above. 
points_sql  TEXT 
Points SQL query as described above. 
start_vid  ANYINTEGER 
Starting point id 
distance  ANYNUMERICAL 
Distance from the start_pid 
directed  BOOLEAN 
(optional). When false the graph is considered as Undirected. Default is true which considers the graph as Directed. 
driving_side  CHAR 

details  BOOLEAN 
(optional). When true the results will include the driving distance to the points with in the distance .
Default is false which ignores other points of the points_sql. 
equicost  BOOLEAN 
(optional). When true the nodes will only appear in the closest start_v list. Default is false which resembles several calls using the single starting point signatures. Tie brakes are arbitrary. 
Returns set of (seq, node, edge, cost, agg_cost)
Column  Type  Description 

seq  INT 
row sequence. 
node  BIGINT 
Identifier of the node within the Distance from start_pid . If details =: true a negative value is the identifier of a point. 
edge  BIGINT 

cost  FLOAT 

agg_cost  FLOAT 

directed
with cost
and reverse_cost
columns¶The examples in this section use the following Graph 1: Directed, with cost and reverse cost
Example:  Left side driving topology 

SELECT * FROM pgr_withPointsDD(
'SELECT id, source, target, cost, reverse_cost FROM edge_table ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
1, 3.8,
driving_side := 'l',
details := true);
seq  node  edge  cost  agg_cost
++++
1  1  1  0  0
2  2  1  0.6  0.6
3  6  4  0.7  1.3
4  5  4  0.3  1.6
5  1  1  1  1.6
6  6  8  1  2.6
7  8  7  1  2.6
8  10  10  1  2.6
9  3  12  0.6  3.2
10  4  6  0.7  3.3
11  7  6  0.3  3.6
12  9  9  1  3.6
13  11  11  1  3.6
14  13  14  1  3.6
(14 rows)
Example:  Does not matter driving side. 

SELECT * FROM pgr_withPointsDD(
'SELECT id, source, target, cost, reverse_cost FROM edge_table ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
1, 3.8,
driving_side := 'b',
details := true);
seq  node  edge  cost  agg_cost
++++
1  1  1  0  0
2  1  1  0.4  0.4
3  2  1  0.6  0.6
4  6  4  0.7  1.3
5  5  4  0.3  1.6
6  6  8  1  2.6
7  8  7  1  2.6
8  10  10  1  2.6
9  3  12  0.6  3.2
10  4  6  0.7  3.3
11  7  6  0.3  3.6
12  9  9  1  3.6
13  11  11  1  3.6
14  13  14  1  3.6
(14 rows)
The queries use the Sample Data network.
History
Indices and tables