# Geotype - WKT - Polygons

**URL:** <https://odm.discourse.group/t/geotype-wkt-polygons/169>\
**Category:** Development\
**Tags:** odm-v2, mapping, polygons\
**Created:** [October 4, 2024, 12:00am UTC](https://odm.discourse.group/t/geotype-wkt-polygons/169 "2024-10-04T00:00:08Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![matthomson](https://avatars.discourse-cdn.com/v4/letter/m/dec6dc/32.png) [@matthomson](https://odm.discourse.group/u/matthomson)\
**Post date:** [October 4, 2024, 12:00am UTC](https://odm.discourse.group/t/geotype-wkt-polygons/169/1 "2024-10-04T00:00:08Z")

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It was brought up today at the working group meeting that it might be beneficial to have the `geotype` header in the `polygons` table standardized.

Currently, the only two geography types that can be specified are “sewer shed” or “health region”.

It was brought up that we may wish to standardize to a specific geography type list:  
0 = GEOMETRY  
1 = POINT  
2 = CURVE  
3 = LINESTRING  
4 = SURFACE  
5 = POLYGON  
6 = COLLECTION  
7 = MULTIPOINT  
8 = MULTICURVE  
9 = MULTILINESTRING  
10 = MULTISURFACE  
11 = MULTIPOLYGON

This led to a discussion around creating a parallel structure to `shedType` and `siteType` in the `polygons` table.

However, because we already record (or ask to record) the well-known text (WKT) file with the polygon, this information would be duplicated since the number denoting the geography type is already in the WKT. It was suggested that we may still add the above list as parts for validation purposes.

@Sorin @jeandavidt - does this summarize the conversion well?

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**Author:** ![Sorin](https://yyz2.discourse-cdn.com/free1/user_avatar/odm.discourse.group/sorin/32/52_2.png) [@Sorin](https://odm.discourse.group/u/Sorin)\
**Post date:** [October 4, 2024, 4:17am UTC](https://odm.discourse.group/t/geotype-wkt-polygons/169/2 "2024-10-04T04:17:55Z")

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Indeed, that was the gist of the discussion. See, for example, the thread at [well known text - Why do single-part WKT polygon vertices require double parentheses? - Geographic Information Systems Stack Exchange](https://gis.stackexchange.com/questions/433052/why-do-single-part-wkt-polygon-vertices-require-double-parentheses) for examples of WKT and why it would be superfluous to store the type in the geoType column.  
On the other hand, since we have only two values for the geoType and the field is mandatory, it remains to be discussed if we should expand the list, to make it comprehensive for what we want to store in it, or remove its mandatory-ness.

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**Author:** ![matthomson](https://avatars.discourse-cdn.com/v4/letter/m/dec6dc/32.png) [@matthomson](https://odm.discourse.group/u/matthomson)\
**Post date:** [October 24, 2024, 5:22pm UTC](https://odm.discourse.group/t/geotype-wkt-polygons/169/3 "2024-10-24T17:22:35Z")

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