[mapguide-internals] ogr postgis layer problems

[Frank Warmerdam]

Traian Stanev wrote:
> Hi Frank,
>  
> I am applying the FID filter as an attribute filter, using the following 
> call:
>  
> 
> layer->SetAttributeFilter(mbattrsql);
> 
> where layer is an OGRLayer. After that in the case of Select I call 
> layer->ResetReading() before reading the resulting features. I basically 
> treat the string representation of the FDO attribute filter (mbattrsql) 
> as a valid OGR filter. I don't know what OGR does underneath, may be it 
> uses ExecuteSQL -- you tell me. 

Traian,

If you aren't calling it explicitly then it isn't happening and this isn't
the problem.

 > I do acknowledge that doing this for
> attribute filters is extremely hopeful (meaning that the assumption that 
> it works is based on pure belief in miracles :-), but I did do some 
> limited testing and other attribute filters worked well as layer filters 
> in MapGuide.
> 
> In general I spent very little time on the filter handling in the OGR 
> provider since I didn't have much time and wasn't sure how useful it 
> would be. I'm willing to fix it up if it turns out to be the problem. In 
> particular, I didn't bother to support queries which are more than a 
> combination of one spatial filter and one attribute filter -- which is 
> about par for most MapGuide operations.

I don't see any obvious sign of problems in what you are doing.

> Traian
> 
> P.S. the provider Paul is using is compiled with GDAL 1.3.2.

I'd encourage trying it with GDAL 1.4.0 if that is practical.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGeo, http://osgeo.org