Re: Africa Digest, Vol 136, Issue 13

classic Classic list List threaded Threaded
1 message Options
Reply | Threaded
Open this post in threaded view
|

Re: Africa Digest, Vol 136, Issue 13

Gerhard Brits
Hi

You can also try to have a look at the content of the SDO_GEOMTERY.

The Oracle geometry consists of 4 elements.

1. The type of geographic feature
2. The SRID
3. The element array. This gives you an idea of how the coordinates link together.
4. the Ordinate array.  Which is a list of x, y depending on the data a z.

So you can investigate 3 and 4. Oracle does have built in methods to query these elements. I think it should work to have a look at the element array. If your element array is more complex that something like (1,2,1). Meaning coordinates link one to the other. then you have more than one boundary per geometry. Also is your feature type is not 2003 or 3003 it can also indicate a complex geometry.

You can also try to use SDO_GEOM.RELATE("GEOMTERY_COLUMN", 'mask=TOUCH+EQUAL', "GEOMTERY_COLUMN", tolerance) using the geometry of the same table and maybe count the amount of return you get. OR  use PL/SQL loop trough the table comparing each geometry to itself.

Hope the above helps.

Regards


-----Original Message-----
From: Africa [mailto:[hidden email]] On Behalf Of [hidden email]
Sent: 13 June 2018 09:00 PM
To: [hidden email]
Subject: Africa Digest, Vol 136, Issue 13

Send Africa mailing list submissions to
        [hidden email]

To subscribe or unsubscribe via the World Wide Web, visit
        https://lists.osgeo.org/mailman/listinfo/africa
or, via email, send a message with subject or body 'help' to
        [hidden email]

You can reach the person managing the list at
        [hidden email]

When replying, please edit your Subject line so it is more specific
than "Re: Contents of Africa digest..."


Today's Topics:

   1. Re: Oracle select query to select entities where the geometry
      only has one boundary (Mike Caister)
   2. free Geocoders (Ndamulelo Mudau)
   3. Re: free Geocoders (ZARON Business Solutions)


----------------------------------------------------------------------

Message: 1
Date: Wed, 13 Jun 2018 06:23:24 +0000
From: Mike Caister <[hidden email]>
To: Africa local chapter discussions <[hidden email]>
Subject: Re: [OSGeo Africa] Oracle select query to select entities
        where the geometry only has one boundary
Message-ID: <[hidden email]>
Content-Type: text/plain; charset="utf-8"

Thank you Gavin, I will give it a try.

Regards,

Mike Caister



From: Africa [mailto:[hidden email]] On Behalf Of Gavin Fleming
Sent: 13 June 2018 07:15
To: Africa local chapter discussions <[hidden email]>
Subject: Re: [OSGeo Africa] Oracle select query to select entities where the geometry only has one boundary

Hi Mike

Oracle not being FOSS and with it using the SDO geometry type that I’m not familiar with, I can’t give you the Oracle SQL answer, but the query in PostGIS (which DRDLR should be using :-) ) would be

SELECT * FROM mytable
WHERE ST_NumGeometries(geom) = 1 - - this will exclude multipolygons
            AND ST_NumInteriorRings(geom) = 0 - - this will exclude polygons with holes (interior rings)

Gavin

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/africa/attachments/20180613/55f0dcd1/attachment-0001.html>

------------------------------

Message: 2
Date: Wed, 13 Jun 2018 10:42:39 +0200
From: Ndamulelo Mudau <[hidden email]>
To: [hidden email]
Subject: [OSGeo Africa] free Geocoders
Message-ID:
        <[hidden email]>
Content-Type: text/plain; charset="utf-8"

Good morning,

I've got a list of +-40 thousands addresses to geocode, meaning I cannot do
it manually. I came accross a Google API geocoder which i ended up using
although it did not geocode everything. only the addresses in the right
formats (eg 123 Madiba street, Hatfield, Pretoria 0183) were geocoded.

Is there any geocoder I could use? preferably I want a geocoder that will
look for the full address first, but if it can't return it then it must
roll up and look for the area name and return the centroid.

___
Regards
Mudau N
0829358587
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/africa/attachments/20180613/74d0f825/attachment-0001.html>

------------------------------

Message: 3
Date: Wed, 13 Jun 2018 10:45:26 +0200
From: ZARON Business Solutions <[hidden email]>
To: Africa local chapter discussions <[hidden email]>
Subject: Re: [OSGeo Africa] free Geocoders
Message-ID:
        <CALTTkub0GaS_HKQrKE=rK0S7mj8FALh9=i=[hidden email]>
Content-Type: text/plain; charset="utf-8"

Hi Madau,

Check http://www.gpsvisualizer.com/


Kind regards,



On Wed, Jun 13, 2018 at 10:42 AM, Ndamulelo Mudau <[hidden email]>
wrote:

> Good morning,
>
> I've got a list of +-40 thousands addresses to geocode, meaning I cannot
> do it manually. I came accross a Google API geocoder which i ended up using
> although it did not geocode everything. only the addresses in the right
> formats (eg 123 Madiba street, Hatfield, Pretoria 0183) were geocoded.
>
> Is there any geocoder I could use? preferably I want a geocoder that will
> look for the full address first, but if it can't return it then it must
> roll up and look for the area name and return the centroid.
>
> ___
> Regards
> Mudau N
> 0829358587
>
>
> _______________________________________________
> Africa mailing list
> [hidden email]
> You can UNSUBSCRIBE at https://lists.osgeo.org/mailman/listinfo/africa
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/africa/attachments/20180613/dae5f8b5/attachment-0001.html>

------------------------------

Subject: Digest Footer

_______________________________________________
Africa mailing list
[hidden email]
https://lists.osgeo.org/mailman/listinfo/africa

------------------------------

End of Africa Digest, Vol 136, Issue 13
***************************************
NB: This Email and its contents are subject to the Eskom Holdings SOC Ltd EMAIL LEGAL NOTICE which can be viewed at http://www.eskom.co.za/Pages/Email_Legal_Spam_Disclaimer.aspx
_______________________________________________
Africa mailing list
[hidden email]
You can UNSUBSCRIBE at https://lists.osgeo.org/mailman/listinfo/africa