OGR connection vs shp DATA
yecarrillo at YAHOO.COM
Thu Nov 18 10:36:09 EST 2004
> Advantages of using OGR for shapefile access:
> o OGR is slower than built-in Shapefile support because of many extra
> layers of abstraction and conversion.
> o OGR is slower because it doesn't currently support use of spatial
> indexes for shapefiles while the built-in mapserver shapefile support
> does. (Note: I actually have support for mapserver style spatial indexes
> half implemented in my local development tree, but no ETA).
> o OGR supports "OGR SQL" in the DATA statement, though most effects you
> might accomplish that way can be simulated at least as efficiently using
> MapServer expressions and other mechanisms.
> o You can use OGR style joins, including the ability to join to some
> non-shapefile types of stuff as long as it is supported by OGR. I am
> not sure how OGR joining compares to the built-in mapserver joins that
> work for shapefiles.
> Basically, except for rare circumstances you are better off using the
> built-in shapefile support instead of accessing through OGR.
> Best regards,
Thank You. It is the most clear answer. I'm thinking to support joined shapes
tables and OGR connection format for the next release of Gix Export Tool.
Eduin Yesid Carrillo Vega
yecarrillo at yahoo.com
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