Steve T.,
mapserver gets back all the geometries from postgis and then filters
them in mapserver against the geometry.
Mapserver passes the BBOX for the mapfile to postgis as you noticed
which is not very efficient, but you can override that to the BBOX of
the window using the BBOX substitution variable in the SQL, but this
might not be what you want if you geometry is off screen.
I'm not aware of any way to pass the BBOX of the geometry.
Steve L - can we do this?
So currently, your wfs requests are getting filtered against the
geometry. And there is room for efficiency improvements.
-Steve W
On 1/26/2015 11:15 AM, steve.tout...@inspq.qc.ca wrote:
sorry I'm confused, perhaps I misunderstand what you explained. I don't
understand what you mean by "MapServer does use the supplied geometry,
it’s a matter of where the filter is applied – the database or in
MapServer"
In mapserver log I see
FLTLayerApplyPlainFilterToLayer(): ([shape] within fromText('POLYGON
((-8081644.2511243997141719 5835062.5699599999934435,
-8081707.5505384001880884 5834980.1612889003008604,
-8081638.2794815003871918 5834913.2788891997188330,
-8081533.1785677000880241 5834988.5215889001265168,
-8081644.2511243997141719 5835062.5699599999934435))'))
So this is good, but
A few lines later in the mapserver log, I see that it is not sending the
supplied geometry as filter, it is sending the extent of the mapfile
select ....... where geom_p && ST_GeomFromText('POLYGON((-9239517
5465442,-9239517 9349764,-5565974 9349764,-5565974 5465442,-9239517
5465442))',3857);
So it received the supplied geometry, but it is not using it....
If only BBOX can be used as a spatial operator, it is not good for our
needs. We really need to know what features are inside a user defined
polygon.
*"Lime, Steve D (MNIT)" <steve.l...@state.mn.us>*
2015-01-26 10:56
A
"steve.tout...@inspq.qc.ca" <steve.tout...@inspq.qc.ca>
cc
"mapserver-users@lists.osgeo.org" <mapserver-users@lists.osgeo.org>
Objet
RE: [mapserver-users] Mapserver doesn't send good filter to postgis
MapServer does use the supplied geometry, it’s a matter of where the
filter is applied – the database or in MapServer. This isn’t a new
limitation so others may have more experience with workarounds. Maybe
try also setting a bbox in the filter based on the bbox of the geometry?
Steve
*From:* steve.tout...@inspq.qc.ca [mailto:steve.tout...@inspq.qc.ca] *
Sent:* Monday, January 26, 2015 9:38 AM*
To:* Lime, Steve D (MNIT)*
Cc:* mapserver-users@lists.osgeo.org*
Subject:* RE: [mapserver-users] Mapserver doesn't send good filter to
postgis
I understand the objective of rfc 91, but the most common use case would
be to pass the supplied geometry.....
If mapserver doesn't use the supplied geometry, that means that it
doesn't support spatial filtering.
Our data covers the whole country, not using the supplied geometry means
we can't use mapserver as a wfs server....
Is there something we can do about it? A workaround we could use?
*"Lime, Steve D (MNIT)" <**_steve.l...@state.mn.us_*
<mailto:steve.l...@state.mn.us>*>*
2015-01-26 10:14
A
"_steve.tout...@inspq.qc.ca_ <mailto:steve.tout...@inspq.qc.ca>"
<_steve.tout...@inspq.qc.ca_ <mailto:steve.tout...@inspq.qc.ca>>,
"_mapserver-users@lists.osgeo.org_
<mailto:mapserver-users@lists.osgeo.org>"
<_mapserver-users@lists.osgeo.org_
<mailto:mapserver-users@lists.osgeo.org>>
cc
Objet
RE: [mapserver-users] Mapserver doesn't send good filter to postgis
It’s a limitation in older versions of MapServer where specific backend
optimizations were scattered about the WMS/WFS code. Most of those
optimizations address the most common use cases – I guess this wasn’t
one of them. It’s surprising that at worst the extent of the supplied
geometry isn’t passed (I see a comment in the WFS code about this). The
specific filter intersection test is applied on the MapServer side – the
results are correct, performance can suffer though.
This is being addresses in MapServer 7.0 where more complete filter
translation functions are being supported (RFC 91).
Steve
*
From:* _mapserver-users-bounces@lists.osgeo.org_
<mailto:mapserver-users-boun...@lists.osgeo.org>
[_mailto:mapserver-users-bounces@lists.osgeo.org_] *On Behalf Of
*_steve.tout...@inspq.qc.ca_ <mailto:steve.tout...@inspq.qc.ca>*
Sent:* Monday, January 26, 2015 8:55 AM*
To:* _mapserver-users@lists.osgeo.org_
<mailto:mapserver-users@lists.osgeo.org>*
Subject:* [mapserver-users] Mapserver doesn't send good filter to postgis
Sorry my first post was with an inapprpriate title......
I'm using mapserver 6.4.1 and postgis 2.1
using OpenLayers 2.13.1 I draw a small polygon that I use for a within
spatial filter of a WFS getfeature request. The problem is that
mapserver is not sending this polygon to postgis, it is sending the
extent of the mapfile as filter...
The wfs POST Request (created and send by OpenLayers client)
<ogc:Filter
xmlns:ogc="_http://www.opengis.net/ogc_";><ogc:Within><ogc:PropertyName>msGeometry</ogc:PropertyName><gml:Polygon
xmlns:gml="_http://www.opengis.net/gml_";
srsName="urn:ogc:def:crs:EPSG::3857"><gml:exterior><gml:LinearRing><gml:posList>-8081644.2511244
5835062.56996 -8081707.5505384 5834980.1612889 -8081638.2794815
5834913.2788892 -8081533.1785677 5834988.5215889 -8081644.2511244
5835062.56996</gml:posList></gml:LinearRing></gml:exterior></gml:Polygon></ogc:Within></ogc:Filter>
In Mapserver log, I see
FLTLayerApplyPlainFilterToLayer(): ([shape] within fromText('POLYGON
((-8081644.2511243997141719 5835062.5699599999934435,
-8081707.5505384001880884 5834980.1612889003008604,
-8081638.2794815003871918 5834913.2788891997188330,
-8081533.1785677000880241 5834988.5215889001265168,
-8081644.2511243997141719 5835062.5699599999934435))'))
Then a few lines later, I see that it is not sending the polygon
received as filter
select ....... where geom_p && ST_GeomFromText('POLYGON((-9239517
5465442,-9239517 9349764,-5565974 9349764,-5565974 5465442,-9239517
5465442))',3857);
See the polygon definition is different, postgis receive the extent
defined in the mapfile
EXTENT -9239517 5465442 -5565974 9349764
And, in postgis log I see this query, See the
select ....... where geom_p && ST_GeomFromText('POLYGON((-9239517
5465442,-9239517 9349764,-5565974 9349764,-5565974 5465442,-9239517
5465442))',3857);
Why Mapserver is not sending the polygon received as filter to postgis?
Thanks!
/Steve Toutant, M. Sc./
Analyste en géomatique
Secteur environnement
Direction de la santé environnementale et de la toxicologie
Institut national de santé publique du Québec
Tél.: 418 646-6777 poste 30015
Téléc.: 418 644-4593_
__steve.tout...@inspq.qc.ca_ <mailto:steve.tout...@inspq.qc.ca>_
__http://www.inspq.qc.ca_ <http://www.inspq.qc.ca/>_
__http://www.monclimatmasante.qc.ca_ <http://www.monclimatmasante.qc.ca/>
/Pour me rejoindre par courrier/
Service de l'infrastructure et du réseau
Direction des technologies de l'information
Ministère de la Sécurité Publique
2525 boul. Laurier, 2e étage
Tour Laurentides
Québec, G1V 2L2
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