[postgis-users] Understanding use cases of brilliant PostGIS scripts

[Shaozhong SHI]

I am interested in what a data quality assurance expert can use these to
assess in the context of data quality assurance.


Can anyone expand further on the use of following scripts for assessment of
network data?


Though there be a lot of solutions available, there is a lack of literature
on the uses of such brilliant codes.


Grouping connected linestrings in PostGIS?
<https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgis.stackexchange.com%2Fquestions%2F94203%2Fgrouping-connected-linestrings-in-postgis&data=04%7C01%7Cshaozhong.shi%40os.uk%7C5031d35b4b9148e0985608d9f520c5ef%7C7988742dc5434b9a87a910a7b354d289%7C0%7C0%7C637810343364343710%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=wxnY0o8kdeeGS2rPjtqYSoySV5VkSBbWC4sJVluoRFU%3D&reserved=0>Grouping
connected linestrings in PostGIS? - Geographic Information Systems Stack
Exchange
<https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgis.stackexchange.com%2Fquestions%2F94203%2Fgrouping-connected-linestrings-in-postgis&data=04%7C01%7Cshaozhong.shi%40os.uk%7C5031d35b4b9148e0985608d9f520c5ef%7C7988742dc5434b9a87a910a7b354d289%7C0%7C0%7C637810343364343710%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=wxnY0o8kdeeGS2rPjtqYSoySV5VkSBbWC4sJVluoRFU%3D&reserved=0>
This looks as though it could be very useful to determine the size of
isolated networks, something that is required to help with the decision as
to how serious a break in the network is. Creating polygons from line
segments using PostgreSQL and PostGIS
<https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgis.stackexchange.com%2Fquestions%2F144866%2Fcreating-polygons-from-line-segments-using-postgresql-and-postgis&data=04%7C01%7Cshaozhong.shi%40os.uk%7C5031d35b4b9148e0985608d9f520c5ef%7C7988742dc5434b9a87a910a7b354d289%7C0%7C0%7C637810343364343710%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=2BWWXXcroBSHIoDEzic9M5JINCCT%2BE%2Bk32UdWhTLIEI%3D&reserved=0>qgis
- Creating polygons from line segments using PostgreSQL and PostGIS -
Geographic Information Systems Stack Exchange
<https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgis.stackexchange.com%2Fquestions%2F144866%2Fcreating-polygons-from-line-segments-using-postgresql-and-postgis&data=04%7C01%7Cshaozhong.shi%40os.uk%7C5031d35b4b9148e0985608d9f520c5ef%7C7988742dc5434b9a87a910a7b354d289%7C0%7C0%7C637810343364343710%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=2BWWXXcroBSHIoDEzic9M5JINCCT%2BE%2Bk32UdWhTLIEI%3D&reserved=0>Having
read the limited documentation on ST_Polygonize andST_BuildArea it is not
clear to me whether these will create polygons only from single closed
lines or from multiple lines that form the boundary of a polygon. I think
you will have to create a small test data set of line geometries and
experiment.
Something like the example in your link.
[image: line geometry]  Are these useful in relation to what we do?  As
these just codes, what are the likely applications beyond the codes
themselves.  Any gaps need to be filled. Regards,

David
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20220310/c3f8270f/attachment.html>