[postgis-devel] [PostGIS] #1471: gist geometric equality operator - for geometry uniqueness constraints

[PostGIS]

#1471: gist geometric equality operator - for geometry uniqueness constraints
---------------------+------------------------------------------------------
 Reporter:  robe     |       Owner:  pramsey       
     Type:  defect   |      Status:  new           
 Priority:  medium   |   Milestone:  PostGIS Future
Component:  postgis  |     Version:  trunk         
 Keywords:           |  
---------------------+------------------------------------------------------
 The geometric equality operator we used to have in 1.3 (~=) would be even
 more useful now.  We can't call it ~= since that has already changed
 definition so much and is now just a bounding box equality (and not even
 that much because our bounding boxes are floats instead of the double
 precision of the geometry)

 Something like  == might be a possible choice for bringing back the good
 old geometric equality ~= (NOTE this requies it have a RECHECK on it.

 The main benefit would be to be able to use exclusion constraints
 (introduced in PostgreSQL 9.0) to enforce geometry uniqueness.  Right now
 there is no guaranteed way of doing this and EXCLUSION CONSTRAINTS won't
 work with functions (so ST_OrderingEquals is out of the question) -- they
 have to be operators.

 http://www.postgresql.org/docs/9.0/static/sql-createtable.html#SQL-
 CREATETABLE-EXCLUDE

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/1471>
PostGIS <http://trac.osgeo.org/postgis/>
The PostGIS Trac is used for bug, enhancement & task tracking, a user and developer wiki, and a view into the subversion code repository of PostGIS project.