[postgis-tickets] [PostGIS] #3000: Edge linking does not use index

[PostGIS]

#3000: Edge linking does not use index
-------------------------+--------------------------------------------------
 Reporter:  strk         |       Owner:  strk         
     Type:  enhancement  |      Status:  new          
 Priority:  medium       |   Milestone:  PostGIS 2.2.0
Component:  topology     |     Version:  trunk        
 Keywords:  performance  |  
-------------------------+--------------------------------------------------
 I've found sequencial scans on the edge table during topology building
 which are due to the UPDATE queries to edges performed to set edge
 linking. The queries are of this form:

 {{{
 UPDATE topo_ulfareale.edge_data SET next_right_edge = -1175,
 abs_next_right_edge = 1175 WHERE edge_id != 1175 A
 ND next_right_edge = -1114;
 }}}

 But being there no index on next_right_edge the planner goes for a
 sequencial scan.

 See also #2993 for skipping the UPDATE completely (but the SELECT query
 would still be needed so this ticket has its own right)

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/3000>
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