Related to #44819
This fix addresses an issue(#44819) where the offset parameter did not
work correctly during searches when multiple results had identical
scores. The problem occurred because results with equal scores were not
consistently ordered, leading to unpredictable pagination behavior.
The solution adds a new sorting step (SortEqualScoresByPks) in the
reduce phase that sorts results with identical scores by their primary
keys in ascending order. This ensures deterministic ordering and enables
proper offset functionality.
Changes:
- Add SortEqualScoresByPks() to sort results with equal scores by PK
- Add SortEqualScoresOneNQ() to handle per-query sorting logic
- Invoke sorting step after FillPrimaryKey() in Reduce() workflow
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Signed-off-by: Congqi Xia <congqi.xia@zilliz.com>
related: #25324
Search GroupBy function, used to aggregate result entities based on a
specific scalar column.
several points to mention:
1. Temporarliy, the whole groupby is implemented separated from
iterative expr framework **for the first period**
2. In the long term, the groupBy operation will be incorporated into the
iterative expr framework:https://github.com/milvus-io/milvus/pull/28166
3. This pr includes some unrelated mocked interface regarding alterIndex
due to some unworth-to-mention reasons. All these un-associated content
will be removed before the final pr is merged. This version of pr is
only for review
4. All other related details were commented in the files comparison
Signed-off-by: MrPresent-Han <chun.han@zilliz.com>
