fix: Group value is nil(#45418) (#45421)

related: #45418
pr: #45422

Signed-off-by: MrPresent-Han <[email protected]>
Co-authored-by: MrPresent-Han <[email protected]>

Author: MrPresent-Han

internal/proxy/search_reduce_util.go

@@ -514,6 +514,7 @@ func reduceResults(ctx context.Context, toReduceResults []*internalpb.SearchResu
 	}
 
 	if len(validSearchResults) <= 0 {
+		log.Debug("reduced search results is empty, fill in empty result")
 		return fillInEmptyResult(nq), nil
 	}
 

internal/util/function/rerank/util.go

@@ -25,6 +25,7 @@ import (
 	"strings"
 
 	"github.com/milvus-io/milvus-proto/go-api/v2/schemapb"
+	"github.com/milvus-io/milvus/pkg/v2/log"
 	"github.com/milvus-io/milvus/pkg/v2/util/merr"
 	"github.com/milvus-io/milvus/pkg/v2/util/metric"
 	"github.com/milvus-io/milvus/pkg/v2/util/typeutil"
@@ -516,7 +517,8 @@ func genIdGroupingMap(multipSearchResultData []*schemapb.SearchResultData) (map[
 	idGroupValue := map[any]any{}
 	for _, result := range multipSearchResultData {
 		if result.GetGroupByFieldValue() == nil {
-			return nil, fmt.Errorf("Group value is nil")
+			log.Warn("Group value is nil, this is due to empty results in search reduce phase")
+			continue
 		}
 		size := typeutil.GetSizeOfIDs(result.Ids)
 		groupIter := typeutil.GetDataIterator(result.GetGroupByFieldValue())