pgr_astar  Deprecated Signature¶
Warning
This function signature is deprecated!!!
 That means it has been replaced by new signature(s)
 This signature is no longer supported, and may be removed from future versions.
 All code that use this function signature should be converted to use its replacement pgr_aStar.
Name¶
pgr_astar — Returns the shortest path using A* algorithm.
Synopsis¶
The A* (pronounced “A Star”) algorithm is based on Dijkstra’s algorithm with a heuristic that allow it to solve most shortest path problems by evaluation only a subset of the overall graph. Returns a set of pgr_costResult (seq, id1, id2, cost) rows, that make up a path.
pgr_costResult[] pgr_astar(sql text, source integer, target integer,
directed boolean, has_rcost boolean);
Description¶
sql:  a SQL query, which should return a set of rows with the following columns: SELECT id, source, target, cost, x1, y1, x2, y2 [,reverse_cost] FROM edge_table



source:  int4 id of the start point 

target:  int4 id of the end point 

directed:  true if the graph is directed 

has_rcost:  if true, the reverse_cost column of the SQL generated set of rows will be used for the cost of the traversal of the edge in the opposite direction. 
Returns set of pgr_costResult[]:
seq:  row sequence 

id1:  node ID 
id2:  edge ID (1 for the last row) 
cost:  cost to traverse from id1 using id2 
History
 Renamed in version 2.0.0
Examples¶
 Without reverse_cost
SELECT * FROM pgr_AStar(
'SELECT id::INTEGER, source::INTEGER, target::INTEGER, cost, x1, y1, x2, y2
FROM edge_table',
4, 1, false, false);
NOTICE: Deprecated signature of function pgr_astar
seq  id1  id2  cost
+++
0  4  16  1
1  9  9  1
2  6  8  1
3  5  4  1
4  2  1  1
5  1  1  0
(6 rows)
 With reverse_cost
SELECT * FROM pgr_AStar(
'SELECT id::INTEGER, source::INTEGER, target::INTEGER, cost, x1, y1, x2, y2, reverse_cost
FROM edge_table ',
4, 1, true, true);
NOTICE: Deprecated signature of function pgr_astar
seq  id1  id2  cost
+++
0  4  3  1
1  3  2  1
2  2  1  1
3  1  1  0
(4 rows)
The queries use the Sample Data network.