[postgis-users] avoid duplicates with lateral auto join

[Olivier Leprêtre]

Hi,

 

Doing a lateral auto join return cross results like A,B and B,A. Is there a
simple trick to avoid that ?

 

To explain : in such query

 

select o.name,nam1 from 

t1 o,

lateral (select o.name,t1.nam nam1 from t1

where st_overlaps(o.geom,t1.geom)) lat

order by o.name

 

I get results like

 

polygon1       polygon2

polygon2       polygon1

 

because polygon1 overlap polygon2 and conversely.

 

how could I get only one of those pairs ?

 

Thanks,

 

Olivier

 

 

 



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