html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,issue,performed_via_github_app
https://github.com/simonw/sqlite-utils/issues/399#issuecomment-1548913065,https://api.github.com/repos/simonw/sqlite-utils/issues/399,1548913065,IC_kwDOCGYnMM5cUomp,433780,2023-05-16T03:11:03Z,2023-05-16T03:11:52Z,NONE,"Using this thread and some [other resources](https://sqlite-utils.datasette.io/en/stable/cli.html#spatialite-helpers) I managed to cobble together a couple of sqlite-utils lines to add a geometry column for a table that already has a lat/lng column.
```
# add a geometry column
sqlite-utils add-geometry-column [db name] [table name] geometry --type POINT --srid 4326
# add a point for each row to geometry column
sqlite-utils --load-extension=spatialite [db name] 'update [table name] SET Geometry=MakePoint(longitude, latitude, 4326);'
```","{""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1124731464,
https://github.com/simonw/sqlite-utils/issues/399#issuecomment-1030807433,https://api.github.com/repos/simonw/sqlite-utils/issues/399,1030807433,IC_kwDOCGYnMM49cN-J,6025893,2022-02-06T10:54:09Z,2022-02-06T10:54:09Z,NONE,"> Interesting that some accept an SRID and others do not - presumably GeomFromGeoJSON() always uses SRID=4326?
The ewtk/ewkb ones don't accept an SRID is because ewkt encodes the SRID in the string, so you would do this with a wkt string:
`GeomFromText('POINT(529090 179645)', 27700)`
but for ewkt it would be
`GeomFromEWKT('SRID=27700;POINT(529090 179645)')`
The specs for KML and GeoJSON specify a Coordinate Reference System for the format
- https://datatracker.ietf.org/doc/html/rfc7946#section-4
- https://docs.opengeospatial.org/is/12-007r2/12-007r2.html#1274
GML can specify the SRID in the XML at feature level e.g:
```
529090, 179645
```
There's a few more obscure formats in there, but broadly I think it is safe to assume an SRID param exists on the function for cases where the SRID is not implied by or specified in the input format.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1124731464,