wgtmac commented on code in PR #494: URL: https://github.com/apache/parquet-format/pull/494#discussion_r2065270832
########## Geospatial.md: ########## @@ -94,6 +94,39 @@ Bounding box is defined as the thrift struct below in the representation of min/max value pair of coordinates from each axis. Note that X and Y Values are always present. Z and M are omitted for 2D geospatial instances. +Writers should follow the guidelines below when calculating bounding boxes in +the presence of edge cases. + +* `null` instance: Skip it and continue processing the remaining + geospatial instances. Do not produce a bounding box if all instances are null. +* Non-`null` instance with [invalid geospatial values](#invalid-geospatial-values): + * X and Y: Skip any invalid X or Y value and continue processing the + remaining X or Y values. Do not produce a bounding box if all X or all Y + values are invalid. + + * Z: Skip any invalid Z value and continue processing the remaining Z values. + Omit Z from the bounding box if all Z values are invalid. + + * M: Skip any invalid M value and continue processing the remaining M values. + Omit M from the bounding box if all M values are invalid. + +Readers should follow the guidelines below when examining bounding boxes. +Parquet does not permit `null` or `NaN` values in bounding boxes, whether at +the overall bounding box level or within individual coordinate fields. + +* No bounding box: No assumptions can be made about the presence or validity + of coordinate values. Readers may need to load all individual coordinate + values for validation. + +* A bounding box is present: + * X and Y: Both X and Y of the bounding box must be present. Review Comment: The guidelines here is for readers to determine whether a bbox is reliable. So I think `value is present` is not sufficient. -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
