[gdal-dev] DBF indexing?

Frank Warmerdam warmerdam at pobox.com
Wed Apr 25 20:53:57 EDT 2012


Yes, but only in a very restricted fashion.  The shapefile driver docs says:

"""Currently the OGR Shapefile driver only supports attribute indexes
for looking up specific values in a unique key column. To create an
attribute index for a column issue an SQL command of the form "CREATE
INDEX ON tablename USING fieldname". To drop the attribute indexes
issue a command of the form "DROP INDEX ON tablename". The attribute
index will accelerate WHERE clause searches of the form "fieldname =
value". The attribute index is actually stored as a mapinfo format
index and is not compatible with any other shapefile applications."""

I think that is still accurate.

Best regards,

On Wed, Apr 25, 2012 at 5:38 PM, William Kyngesburye
<woklist at kyngchaos.com> wrote:
> Is it possible to index fields in a DBF, and does GDAL support that for a JOIN?
> -----
> William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
> http://www.kyngchaos.com/
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