Connect to ESRI Personal Geodatabase
Ken Lord
kenlord at GMAIL.COM
Wed Jul 6 17:17:20 PDT 2005
Nice to see this topic is gaining interest!
Mike, Craig, Alex, I'll forward Frank's quote to you plus some
questions/answers that have gone back and forth between us. Perhaps there's
some important issues or features I missed that you guys could toss into
this.
Over here, (BGC Engineering Inc in Vancouver BC), we'd love to see this
project go ahead with a couple partners to share the cost.
I'll be out of the office (camping in the Okanagen!) between July 8th and
July 20th. During that time if anyone needs to contact me regarding this
endevour, please contact Gerry James ( gjames AT
bgcengineering.ca<http://bgcengineering.ca>).
Cheers,
Ken Lord
Vancouver BC
On 7/6/05, Frank Warmerdam <fwarmerdam at gmail.com> wrote:
>
> On 7/6/05, Frank Warmerdam <fwarmerdam at gmail.com> wrote:
> > On 7/6/05, Mike Davis <mike.and.kerry at gmail.com> wrote:
> > > Funding things where I work is like pulling teeth, but I will inquire
> > > with the "powers that be" to see if it is possible, this is a feature
> > > we would really like to have (especially if the performace is close to
> > > that of shapefiles).
>
> Mike,
>
> There are two main issues affecting performance.
>
> 1) Spatial indexing. Personal geodatabase does have a spatial
> index table associated with spatial tables. If we can properly utilize
> this we ought to be able to grab small spatial regions out of big tables
> effeciently. If not, it will be as corresponding slow as a shapefile would
>
> be without a spatial index. I'm not really confident I can utilize the
> spatial index yet though. I looked at a sample file Howard provided,
> and the index table just had 0's and -1's in the spatial index table.
> I don't know if I was using too old a version of MS Access to look at it,
> or if it wasn't built or what.
>
> 2) ODBC and OGR translation overhead. Both of these layers add
> significant performance drag.
>
> I can't give any real guarantees for performance, but if we can get
> spatial indexing working it shouldn't be too much worse than direct
> shapefiles.
>
> Best regards,
> --
> ---------------------------------------+--------------------------------------
>
> 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 | Geospatial Programmer for Rent
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/mapserver-users/attachments/20050706/c3e49313/attachment.htm>
More information about the MapServer-users
mailing list