RussellSpitzer commented on a change in pull request #4301:
URL: https://github.com/apache/iceberg/pull/4301#discussion_r834799417
##########
File path: format/spec.md
##########
@@ -193,6 +193,13 @@ Notes:
For details on how to serialize a schema to JSON, see Appendix C.
+#### Default value
+
+Default value can be assigned to top-level columns or nested fields when they
are added to an Iceberg table as part of the schema evolution. The first time a
default value is added, this default value is used to read rows belonging to
the files that lack the column (i.e. the files were written before the column
is added), this default value will also be the default value for the column if
user later inserts new rows without specifying the column.
Review comment:
I think you can think of this doc as if you were trying to implement
Iceberg yourself. Whatever we write here should be all of the information
required to write a brand new implementation.
--
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]
