"best" data format for attribute searches

[Frank Warmerdam]

On 7/18/05, Bart van den Eijnden <BEN at syncera-itsolutions.nl> wrote:
> Hi list,
> 
> AFAIK Mapserver does not use the Mapinfo attribute indexes.
> 
> I am trying to perform attribute searches on a 25 Mb Mapinfo file and am worried about performance, since the indexes won't be used which will mean scanning the whole data file for every attribute search.
> 
> What would be a wise format to shift to for this type of operation? Or doesn't it make any sense to shift to eg PostGIS because of the way Mapserver does queries to RDBMS's?
> 
> Thanks in advance for any insight on this.

Bart, 

The only non-RDBMS driver in OGR that supports indexed attribute
queries is Shapefiles, and there only exact lookups are indexable.
If you don't want the hassle of setting up a complex RDBMS like
PostGIS you might consider a lightweight equivelent like SQLite but
I do think Postgresql/PostGIS would be the ideal option.

PS. I do have a vague intention of implementing indexed attribute
query support for mapinfo tab files at some point, and the underlying
MITAB does support the index files so it shouldn't be too hard.  But
no timeline on such work. 

Best regards,

-- 
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