Join shape and dbms data: OGR?

[Bart van den Eijnden]

Hi Emil,

the problem with the OGR shapefile connector is (or was) that it does not
use the spatial index (qix) files, so it isn't very fast ...

Question for Frank:
Or did this change as well with the current version :) ? I know you were
planning on doing this ...

Best regards,
Bart

On Tue, 16 Nov 2004 08:21:20 +0100, Emil Zegers
<EZS at SYNCERA-ITSOLUTIONS.NL> wrote:

> Hello Michael,
>
> I have a question for you about this approach: when using this kind of
> join were you able to classify data based on the joined attributes and
> display this in the map image?
>
> I'm asking this because with normal join operation it is not possible to
> create thematic maps based on the joined attributes.
>
> If classifcation works based on this approach the enhancement request I
> put in bugzilla (http://mapserver.gis.umn.edu/bugs/show_bug.cgi?id=674)
> can be closed.
>
> I would be very happy if classifying on joined attributes works this way
> (had no time to test this approach yet).
>
> Regards,
>
> Emil Zegers
>
>
> Hi Frank,
>
> thanks for your answer. It is working perfectly now.
>
> For the moment it is only one table i want to join to the geometry of
> the shp-file, so at first
> sight performance is good, but i will play with the indexes a little.
>
> For all who have to use a similar approach here's a mapfile snipplet:
>
>    LAYER
>      ...
>      CONNECTIONTYPE OGR
>      CONNECTION "c:\mstest\data\fnpf.shp"  # shapefile holding only
> geometry and PID in .dbf
>      DATA "SELECT * FROM fnpf LEFT JOIN 'ODBC:fnp'.fnp ON
> fnpf.PID=fnp.PID"
>       # join to systemDSN fnp (here msaccess-db "fnp.mdb" with table
> fnp) on attribute PID,
>       # now all fields of the db are also accessible for mapserver, e.g.
> "AZJAHR"
>      LABELITEM "AZJAHR"
>      ...
>    END
>
> Thanks, Michael
>
>



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