[QGIS-trac] Re: [Quantum GIS] #62: Qgis only supports postgres keys of type int

[Quantum GIS]

#62: Qgis only supports postgres keys of type int
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   Reporter:  g_j_m                             |              Owner:  jef          
       Type:  patch                             |             Status:  new          
   Priority:  major: does not work as expected  |          Milestone:  Version 1.6.0
  Component:  Data Provider                     |            Version:  Trunk        
   Keywords:                                    |   Platform_version:               
   Platform:  All                               |           Must_fix:  No           
Status_info:  0                                 |  
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Comment(by willfurnass):

 > The feature ids are necessary to identify which feature is to be deleted
 or updated.  The table/view is not only queried once, but eg. for  each
 render operation with the current extent in the where clause.  And in
 every query each feature is supposed to have the same id as in the
 previous queries.  I'm not sure how that should work with sequences in
 views.

 Interestingly both of the following views can be loaded by uDig.

 CREATE VIEW myview AS ( SELECT zone_ref,
 ST_ConvexHull(ST_Collect(wkb_geometry)) FROM table_of_points GROUP BY
 zone_ref);

 CREATE VIEW myview_with_id AS ( SELECT nextval('some_seq'), zone_ref,
 ST_ConvexHull(ST_Collect(wkb_geometry)) FROM table_of_points GROUP BY
 zone_ref);

 Does anyone know how uDig internally handles the rendering and
 manipulation of tables/views lacking a UNIQUE constraint?  Would it be
 possible to allow for the viewing of such relations in some sort of read-
 only mode?  Apologies if I'm missing something obvious here.

-- 
Ticket URL: <http://trac.osgeo.org/qgis/ticket/62#comment:19>
Quantum GIS <http://qgis.org>
Quantum GIS is an Open Source GIS viewer/editor supporting OGR, PostGIS, and GRASS formats