clintropolis commented on code in PR #16789: URL: https://github.com/apache/druid/pull/16789#discussion_r1689540843
########## docs/querying/arrays.md: ########## @@ -169,6 +133,39 @@ GROUP BY 1,2,3,4,5 PARTITIONED BY DAY ``` +#### `arrayIngestMode` + +For seamless backwards compatible behavior with Druid versions older than 31, there is an `arrayIngestMode` query context flag. + +When `arrayIngestMode` is `array`, SQL ARRAY types are stored using Druid array columns. This is recommended for new +tables and the default configuration for Druid 31 and newer. + +When `arrayIngestMode` is `mvd` (legacy), SQL `VARCHAR ARRAY` are implicitly wrapped in [`ARRAY_TO_MV`](sql-functions.md#array_to_mv). +This causes them to be stored as [multi-value strings](multi-value-dimensions.md), using the same `STRING` column type +as regular scalar strings. SQL `BIGINT ARRAY` and `DOUBLE ARRAY` cannot be loaded under `arrayIngestMode: mvd`. This +mode is not recommended and will be removed in a future release, but provided for backwards compatibility. + +When `arrayIngestMode` is `none`, Druid throws an exception when trying to store any type of arrays. This mode is most Review Comment: makes sense to me to drop it since I can't think of a very strong use case to keep it around. -- 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: commits-unsubscr...@druid.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@druid.apache.org For additional commands, e-mail: commits-h...@druid.apache.org
