Skip to Main Content

Breadcrumb

Question and Answer

Connor McDonald

Thanks for the question.

Asked: December 08, 2023 - 8:43 pm UTC

Last updated: December 08, 2023 - 8:43 pm UTC

Version:

Viewed 1000+ times

You Asked

Greetings,
I have created a map in Oracle APEX where the user can click and get the lat and long and drop a pin there. Now, I want to find which congressional district the pin was dropped in. I have a table with all congressional districts, but that is geojson data that gives polygons for the congressional districts. Is there a way for me to search a congressional district using lat and long?
Your help will be greatly appreciated
TIA
Vatsa

and we said...

Yes, you can query for containment using a spatial operator as described here: https://docs.oracle.com/en/database/oracle/oracle-database/19/spatl/spatial-operators-reference.html You can try it with this LiveLabs self-paced workshop: https://apexapps.oracle.com/pls/apex/r/dbpm/livelabs/view-workshop?wid=736 see Lab 4 Task 2 for containment queries.

Rating

  (5 ratings)

Comments

Thanks for your response.

Vatsa, December 11, 2023 - 3:07 pm UTC

I forgot to mention that the polygon data for the congressional districts in the table is ia CLOB and not SDO_GEOMETRY. Given a lat and long I want to find out which congressional district are those coordinates in.
Sorry for not being clear the first time.

Thanks
Vatsa

convert wkt to sdo_geometry

good luck, December 17, 2023 - 12:07 pm UTC

If you want to do spatial queries, you need to use sdo_geometry objects. You can convert the clob to a polygon dynamically in the query using the function sdo_util.from_wktgeometry

sdo_util.from_wktgeometry(your_clob_column)

Load geojson as SDO_GEOMETRY

Karin Patenge, January 08, 2024 - 8:49 am UTC

Vatsa,
Besides the conversion functions provided by the SDO_UTIL package, you can also load GeoJSON data via Oracle Spatial Studio. It automatically creates SDO_GEOMETRY objects from your GeoJSON.
Then, simply use SDO_RELATE with mask=INSIDE/ANYINTERACT or SDO_INSIDE/SDO_ANYINTERACT get your containment question answered.
Karin

Thanks for your response.

Vatsa, April 30, 2024 - 12:23 pm UTC

I converted the BLOB column to SDO_GEOMETRY using the function, but when I tried to plot the polygon using the converted column it does not draw the polygon. So, I am not sure if the conversion has happened correctly or if I am missing something.
more

Connor and Chris don't just spend all day on AskTOM. You can also catch regular content via Connor's blog and Chris's blog. Or if video is more your thing, check out Connor's latest video and Chris's latest video from their Youtube channels. And of course, keep up to date with AskTOM via the official twitter account.