[postgis-users] Examples SQL for spatial searches in post gis eg intersect

[Maher_Karim at dorsch.com.jo]

Hi Mohammed,

You can use this example as a guide for you.
select count(*) from layer1,layer2 where layer1.the_geom&&layer2.the_geom 
and intersects(layer1.the_geom,layer2.the_geom)

you should use the "layer1.the_geom&&layer2.the_geom" because it will 
reduce the query time 

Regards
Maher Abdel Karim
GIS systems analyst/Programmer
Dorsch Water and Environment





"Mohammed Wahead" <Mohammed.Wahead at cadcorp.com>
Sent by: postgis-users-bounces at postgis.refractions.net
04/03/2007 05:32 PM
Please respond to PostGIS Users Discussion
 
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        Subject:        [postgis-users] Examples SQL for spatial searches 
in post gis eg  intersect

Hi folks, 
Can anyone point mw in the right direction. I would like examples of SQL 
syntax for running spatial searches in postgis. For example what is the 
SQL for determining which spatial features intersect with another spatial 
feature.
Thanks. 
Mohammed Wahead 
"Subscribe to Cadcorp eNews at www.cadcorp.com."

GIS & RDBMS Specialist
Cadcorp
Computer Aided Development Corporation Ltd Sterling Court,
Norton Road,
Stevenage, Herts,
SG1 2JY, UK
Tel: +44 (0)1438 731440
Fax: +44 (0)1438 747997 



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