[Gdal-dev] PostGIS Driver Performance

[Carl Anderson]

Frank Warmerdam wrote:

>On 7/28/05, Oleg Semykin <oss-dev at rambler.ru> wrote:
>  
>
>>Hi Craig!
>>
>>Why the PostgreSQL driver loads all non-system tables from the database
>>as layers? When we have a lot of tables this results in too big
>>overhead. When we are working with PostGIS all layers are listed in the
>>geometry_columns table and we can use it to prepare a list of tables to
>>load. I can modify the driver to load only layers from the
>>geometry_columns table when we have PostGIS and fallback to the old
>>behaviour when we have plain PostgreSQL.
>>    
>>
>
>Oleg, 
>
>I would be agreeable to such a change in the behavior of 
>OGRPGDataSource::Open().  
>
>Best regards,
>  
>
As a longer term goal it might be nice to add an accessor function for 
the list of  layers available at the OGR level and to allow drivers to 
defer populating it until requested.  So direct access to the array of 
available layers would be deprecated.


C.


-- 
Carl Anderson
GIS Manager Fulton County, Georgia
carl.anderson at co.fulton.ga.us
404.730.8026



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