enhance: add logs for count(*) (#43001)

Signed-off-by: Wei Liu <wei.liu@zilliz.com>

internal/proxy/impl.go

@@ -34,6 +34,7 @@ import (
 	"go.opentelemetry.io/otel/trace"
 	"go.uber.org/zap"
 	"golang.org/x/sync/errgroup"
+	"google.golang.org/protobuf/encoding/protojson"
 	"google.golang.org/protobuf/proto"
 
 	"github.com/milvus-io/milvus-proto/go-api/v2/commonpb"
@@ -3884,6 +3885,11 @@ func (node *Proxy) Query(ctx context.Context, request *milvuspb.QueryRequest) (*
 	})
 	SetReportValue(res.Status, v)
 	metrics.ProxyReportValue.WithLabelValues(nodeID, hookutil.OpTypeQuery, request.DbName, username).Add(float64(v))
+
+	if log.Ctx(ctx).Core().Enabled(zap.DebugLevel) && matchCountRule(request.GetOutputFields()) {
+		r, _ := protojson.Marshal(res)
+		log.Ctx(ctx).Debug("Count result", zap.String("result", string(r)))
+	}
 	return res, nil
 }
 

internal/querynodev2/delegator/delegator.go

@@ -21,6 +21,7 @@ import (
 	"context"
 	"fmt"
 	"path"
+	"slices"
 	"strconv"
 	"sync"
 	"time"
@@ -665,6 +666,23 @@ func (sd *shardDelegator) Query(ctx context.Context, req *querypb.QueryRequest)
 	}
 
 	log.Debug("Delegator Query done")
+	if log.Core().Enabled(zap.DebugLevel) {
+		sealedIDs := lo.FlatMap(sealed, func(item SnapshotItem, _ int) []int64 {
+			return lo.Map(item.Segments, func(segment SegmentEntry, _ int) int64 {
+				return segment.SegmentID
+			})
+		})
+		slices.Sort(sealedIDs)
+		growingIDs := lo.Map(growing, func(item SegmentEntry, _ int) int64 {
+			return item.SegmentID
+		})
+		slices.Sort(growingIDs)
+		log.Debug("execute count on segments...",
+			zap.Int64s("sealedIDs", sealedIDs),
+			zap.Int64s("growingIDs", growingIDs),
+			zap.Int64("targetVersion", sd.distribution.queryView.version),
+		)
+	}
 
 	return results, nil
 }

internal/querynodev2/segments/retrieve.go

@@ -67,6 +67,25 @@ func retrieveOnSegments(ctx context.Context, mgr *Manager, segments []Segment, s
 		if err != nil {
 			return err
 		}
+
+		log := log.Ctx(ctx)
+		if log.Core().Enabled(zap.DebugLevel) && req.GetReq().GetIsCount() {
+			allRetrieveCount := result.AllRetrieveCount
+			countRet := result.GetFieldsData()[0].GetScalars().GetLongData().GetData()[0]
+			if allRetrieveCount != countRet {
+				log.Debug("count segment done with delete",
+					zap.String("channel", s.LoadInfo().GetInsertChannel()),
+					zap.Int64("segmentID", s.ID()),
+					zap.Int64("allRetrieveCount", allRetrieveCount),
+					zap.Int64("countRet", countRet))
+			} else {
+				log.Debug("count segment done",
+					zap.String("channel", s.LoadInfo().GetInsertChannel()),
+					zap.Int64("segmentID", s.ID()),
+					zap.Int64("allRetrieveCount", allRetrieveCount),
+					zap.Int64("countRet", countRet))
+			}
+		}
 		resultCh <- RetrieveSegmentResult{
 			result,
 			s,