msPostGISLayerGetExtent should consider layer filter

Previous Topic Next Topic
 
classic Classic list List threaded Threaded
4 messages Options
Reply | Threaded
Open this post in threaded view
|

msPostGISLayerGetExtent should consider layer filter

Tamas Szekeres
Hi Devs,

We would require that msPostGISLayerGetExtent would apply the specified filter when calculating the layer extent. This would probably be happen by appending the "where" clause from  msPostGISBuildSQLWhere to sqlExtentTemplate. Does this make sense?

I've checked the code and some of the drivers consider the filter and some are not, so I'm not completely sure about the expected behaviour.

Best regards,

Tamas


_______________________________________________
mapserver-dev mailing list
[hidden email]
https://lists.osgeo.org/mailman/listinfo/mapserver-dev
Reply | Threaded
Open this post in threaded view
|

Re: msPostGISLayerGetExtent should consider layer filter

jratike80

Hi,

 

What would be the benefits of appending the ”where”? How often the query is run and can it be slow?

 

-Jukka Rahkonen-

 

Lähettäjä: mapserver-dev [mailto:[hidden email]] Puolesta Tamas Szekeres
Lähetetty: 6. huhtikuuta 2018 10:19
Vastaanottaja: [hidden email]
Aihe: [mapserver-dev] msPostGISLayerGetExtent should consider layer filter

 

Hi Devs,

 

We would require that msPostGISLayerGetExtent would apply the specified filter when calculating the layer extent. This would probably be happen by appending the "where" clause from  msPostGISBuildSQLWhere to sqlExtentTemplate. Does this make sense?

I've checked the code and some of the drivers consider the filter and some are not, so I'm not completely sure about the expected behaviour.

 

Best regards,

 

Tamas

 


_______________________________________________
mapserver-dev mailing list
[hidden email]
https://lists.osgeo.org/mailman/listinfo/mapserver-dev
Reply | Threaded
Open this post in threaded view
|

Re: msPostGISLayerGetExtent should consider layer filter

Tamas Szekeres
I think it would be faster to execute the ST_Extent aggregate on a smaller set of geometries (though it might depend on the implementation).
The benefit would probably be that LayerGetExtent could be used to calculate the actual extent of the layer.

Best regards,

Tamas


2018-04-06 9:24 GMT+02:00 Rahkonen Jukka (MML) <[hidden email]>:

Hi,

 

What would be the benefits of appending the ”where”? How often the query is run and can it be slow?

 

-Jukka Rahkonen-

 

Lähettäjä: mapserver-dev [mailto:[hidden email]] Puolesta Tamas Szekeres
Lähetetty: 6. huhtikuuta 2018 10:19
Vastaanottaja: [hidden email]
Aihe: [mapserver-dev] msPostGISLayerGetExtent should consider layer filter

 

Hi Devs,

 

We would require that msPostGISLayerGetExtent would apply the specified filter when calculating the layer extent. This would probably be happen by appending the "where" clause from  msPostGISBuildSQLWhere to sqlExtentTemplate. Does this make sense?

I've checked the code and some of the drivers consider the filter and some are not, so I'm not completely sure about the expected behaviour.

 

Best regards,

 

Tamas

 



_______________________________________________
mapserver-dev mailing list
[hidden email]
https://lists.osgeo.org/mailman/listinfo/mapserver-dev
Reply | Threaded
Open this post in threaded view
|

Re: msPostGISLayerGetExtent should consider layer filter

Tamas Szekeres
In reply to this post by Tamas Szekeres
Added a PR to implement this one


Best regards,

Tamas


2018-04-08 21:29 GMT+02:00 Tamas Szekeres <[hidden email]>:
I think it would be faster to execute the ST_Extent aggregate on a smaller set of geometries (though it might depend on the implementation).
The benefit would probably be that LayerGetExtent could be used to calculate the actual extent of the layer.

Best regards,

Tamas


2018-04-06 9:24 GMT+02:00 Rahkonen Jukka (MML) <[hidden email]>:

Hi,

 

What would be the benefits of appending the ”where”? How often the query is run and can it be slow?

 

-Jukka Rahkonen-

 

Lähettäjä: mapserver-dev [mailto:[hidden email]] Puolesta Tamas Szekeres
Lähetetty: 6. huhtikuuta 2018 10:19
Vastaanottaja: [hidden email]
Aihe: [mapserver-dev] msPostGISLayerGetExtent should consider layer filter

 

Hi Devs,

 

We would require that msPostGISLayerGetExtent would apply the specified filter when calculating the layer extent. This would probably be happen by appending the "where" clause from  msPostGISBuildSQLWhere to sqlExtentTemplate. Does this make sense?

I've checked the code and some of the drivers consider the filter and some are not, so I'm not completely sure about the expected behaviour.

 

Best regards,

 

Tamas

 




_______________________________________________
mapserver-dev mailing list
[hidden email]
https://lists.osgeo.org/mailman/listinfo/mapserver-dev