nastra commented on code in PR #14234: URL: https://github.com/apache/iceberg/pull/14234#discussion_r3137646175
########## format/spec.md: ########## @@ -683,6 +683,13 @@ Notes: 5. The `content_offset` and `content_size_in_bytes` fields are used to reference a specific blob for direct access to a deletion vector. For deletion vectors, these values are required and must exactly match the `offset` and `length` stored in the Puffin footer for the deletion vector blob. 6. The following field ids are reserved on `data_file`: 141. +###### File-level column statistics + +Per-column metrics used for filtering and planning are stored at **file** granularity on the `data_file` struct. +In v3, implementations use maps such as `value_counts`, `lower_bounds`, and `upper_bounds`, keyed by column id, with bounds serialized as binary (see note 1 under [Data File Fields](#data-file-fields)). +Iceberg v4 adds the optional `content_stats` struct, which holds the same *logical* metrics for primitive leaf columns using nested structs and typed bounds (see [Content Stats](#content-stats)). Review Comment: I've made this more explicit, so stats for primitive types + Geo + Variant are supported. Only nested types (struct, list, map) are not supported, which is also true today in v3 and below -- 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]
