mapleFU commented on code in PR #196: URL: https://github.com/apache/parquet-format/pull/196#discussion_r1150378596
########## README.md: ########## @@ -163,18 +163,25 @@ following rules: [Thrift definition](src/main/thrift/parquet.thrift) in the `ColumnOrder` union. They are summarized here but the Thrift definition is considered authoritative: - * NaNs should not be written to min or max statistics fields. - * If the computed max value is zero (whether negative or positive), - `+0.0` should be written into the max statistics field. - * If the computed min value is zero (whether negative or positive), - `-0.0` should be written into the min statistics field. - - For backwards compatibility when reading files: - * If the min is a NaN, it should be ignored. - * If the max is a NaN, it should be ignored. - * If the min is +0, the row group may contain -0 values as well. - * If the max is -0, the row group may contain +0 values as well. - * When looking for NaN values, min and max should be ignored. + * The following compatibility rules should be applied when reading statistics: + * If the nan_count field is set to > 0 and both min and max are Review Comment: Yes, maybe you are right. My point is that, if we write nan_count or even record count, the program would works well. However, non-float point page would have some size-overhead. Personally, I'd like to use `list<bool>`, because it's easy to implement, and also lightweight. And we can hear others idea. -- 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: dev-unsubscr...@parquet.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org