danielcweeks commented on code in PR #14234: URL: https://github.com/apache/iceberg/pull/14234#discussion_r3237534290
########## format/spec.md: ########## @@ -686,9 +687,31 @@ 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. -###### Bounds for Variant, Geometry, and Geography +##### Field-level Metrics and Statistics -For Variant, values in the `lower_bounds` and `upper_bounds` maps store serialized Variant objects that contain lower or upper bounds respectively. The object keys for the bound-variants are normalized JSON path expressions that uniquely identify a field. The object values are primitive Variant representations of the lower or upper bound for that field. Including bounds for any field is optional and upper and lower bounds must have the same Variant type. +Field statistics (or, interchangeably, metrics) are used when filtering to select data and delete files. + +In v3 and earlier, metrics are stored in maps keyed by column id: `value_counts`, `null_value_counts`, `nan_value_counts`, `lower_bounds` and `upper_bounds`. Review Comment: ```suggestion In v3 and earlier, metrics are stored in maps keyed by field id: `value_counts`, `null_value_counts`, `nan_value_counts`, `lower_bounds` and `upper_bounds`. ``` -- 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]
