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

[Maher Karim]

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.refr|
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|         |           04/03/2007 05:32 PM               |
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  |        Subject: [postgis-users] Examples SQL for spatial searches in post gis eg  intersect                                                      |
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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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