ektravel commented on code in PR #14560: URL: https://github.com/apache/druid/pull/14560#discussion_r1261655175
########## docs/querying/segmentmetadataquery.md: ########## @@ -194,15 +195,20 @@ null if the aggregators are unknown or unmergeable (if merging is enabled). * `rollup` in the result is true/false/null. * When merging is enabled, if some are rollup, others are not, result is null. -## lenientAggregatorMerge +### aggregatorMergeStrategy Conflicts between aggregator metadata across segments can occur if some segments have unknown aggregators, or if -two segments use incompatible aggregators for the same column (e.g. longSum changed to doubleSum). +two segments use incompatible aggregators for the same column (e.g. `longSum` changed to `doubleSum`). The following +aggregator merge strategies are supported: -Aggregators can be merged strictly (the default) or leniently. With strict merging, if there are any segments -with unknown aggregators, or any conflicts of any kind, the merged aggregators list will be `null`. With lenient -merging, segments with unknown aggregators will be ignored, and conflicts between aggregators will only null out -the aggregator for that particular column. +- `strict`: If there are any segments with unknown aggregators, or any conflicts of any kind, the merged aggregators + list will be `null`. +- `lenient`: Segments with unknown aggregators will be ignored, and conflicts between aggregators will only null out +- the aggregator for that particular column. +- `latest`: In the event of conflicts between segments, the aggregator from the most recent segment will be selected + for that particular column. -In particular, with lenient merging, it is possible for an individual column's aggregator to be `null`. This will not -occur with strict merging. + +### lenientAggregatorMerge (deprecated) + +This property is deprecated - consider using [`aggregatorMergeStrategy`](#aggregatormergestrategy) instead. Review Comment: ```suggestion Deprecated. Use [`aggregatorMergeStrategy`](#aggregatormergestrategy) instead. ``` -- 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]
