redblackcoder commented on code in PR #10981: URL: https://github.com/apache/iceberg/pull/10981#discussion_r1946993918
########## format/spec.md: ########## @@ -228,6 +230,30 @@ Notes: For details on how to serialize a schema to JSON, see Appendix C. +[1001]: <https://portal.ogc.org/files/?artifact_id=25355> "OGC Simple feature access" + +##### CRS + +For `geometry` and `geography` types, the parameter C refers to the CRS (coordinate reference system), a mapping of how coordinates refer to locations on Earth. + +The default CRS value `OGC:CRS84` means that the objects must be stored in longitude, latitude based on the WGS84 datum. + +Custom CRS values can be specified by a string of the format `type:identifier`, where `type` is one of the following values: + +* `srid`: [Spatial reference identifier](https://en.wikipedia.org/wiki/Spatial_reference_system#Identifier), `identifier` is the SRID itself. Review Comment: Isn't SRID database specific? From the open specification, it is like following: `SRID`, `AUTH_NAME`, `AUTH_SRID`, `SRTEXT` `OGC:CRS84` corresponds to `AUTH_NAME`=`OGC` and `AUTH_SRID`=`CRS84` Not sure what does SRID:4326 mean from Auth_Name and Auth_Srid perspective. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org
