diff --git a/DEVELOPMENT.md b/DEVELOPMENT.md
index e1c0c1958a..5f40f6a03b 100644
--- a/DEVELOPMENT.md
+++ b/DEVELOPMENT.md
@@ -289,6 +289,10 @@ cd ../../../
 make unittest
 ```
 
+The Apple Silicon compose file uses the Milvus Harbor Docker Hub proxy for
+Pulsar by default. To pull Pulsar directly from Docker Hub instead, set
+`PULSAR_IMAGE=milvusdb/pulsar:v2.8.2-m1`.
+
 For others:
 
 ```shell
diff --git a/client/milvusclient/iterator_option.go b/client/milvusclient/iterator_option.go
index e44a1429ab..ff632fd988 100644
--- a/client/milvusclient/iterator_option.go
+++ b/client/milvusclient/iterator_option.go
@@ -70,6 +70,11 @@ func (opt *searchIteratorOption) WithPartitions(partitionNames ...string) *searc
 	return opt
 }
 
+func (opt *searchIteratorOption) WithNamespace(namespace string) *searchIteratorOption {
+	opt.searchOption.WithNamespace(namespace)
+	return opt
+}
+
 func (opt *searchIteratorOption) WithFilter(expr string) *searchIteratorOption {
 	opt.annRequest.WithFilter(expr)
 	return opt
@@ -166,6 +171,7 @@ type QueryIteratorOption interface {
 type queryIteratorOption struct {
 	collectionName             string
 	partitionNames             []string
+	namespace                  *string
 	outputFields               []string
 	expr                       string
 	batchSize                  int
@@ -178,6 +184,7 @@ func (opt *queryIteratorOption) Request() (*milvuspb.QueryRequest, error) {
 	return &milvuspb.QueryRequest{
 		CollectionName:        opt.collectionName,
 		PartitionNames:        opt.partitionNames,
+		Namespace:             opt.namespace,
 		OutputFields:          opt.outputFields,
 		Expr:                  opt.expr,
 		ConsistencyLevel:      opt.consistencyLevel.CommonConsistencyLevel(),
@@ -211,6 +218,11 @@ func (opt *queryIteratorOption) WithPartitions(partitionNames ...string) *queryI
 	return opt
 }
 
+func (opt *queryIteratorOption) WithNamespace(namespace string) *queryIteratorOption {
+	opt.namespace = &namespace
+	return opt
+}
+
 func (opt *queryIteratorOption) WithFilter(expr string) *queryIteratorOption {
 	opt.expr = expr
 	return opt
diff --git a/client/milvusclient/iterator_test.go b/client/milvusclient/iterator_test.go
index 656b37c8b8..11e2301f5a 100644
--- a/client/milvusclient/iterator_test.go
+++ b/client/milvusclient/iterator_test.go
@@ -47,6 +47,18 @@ func (s *SearchIteratorSuite) SetupSuite() {
 		WithField(entity.NewField().WithName("Vector").WithDataType(entity.FieldTypeFloatVector).WithDim(128))
 }
 
+func (s *SearchIteratorSuite) TestSearchIteratorOptionWithNamespace() {
+	namespace := "tenant_a"
+
+	opt := NewSearchIteratorOption("coll", entity.FloatVector(lo.RepeatBy(128, func(_ int) float32 {
+		return rand.Float32()
+	}))).WithNamespace(namespace)
+	req, err := opt.SearchOption().Request()
+
+	s.Require().NoError(err)
+	s.Equal(namespace, req.GetNamespace())
+}
+
 func (s *SearchIteratorSuite) TestSearchIteratorInit() {
 	ctx := context.Background()
 	s.Run("success", func() {
@@ -431,6 +443,15 @@ func (s *QueryIteratorSuite) SetupSuite() {
 		WithField(entity.NewField().WithName("Name").WithDataType(entity.FieldTypeVarChar).WithMaxLength(256))
 }
 
+func (s *QueryIteratorSuite) TestQueryIteratorOptionWithNamespace() {
+	namespace := "tenant_a"
+
+	req, err := NewQueryIteratorOption("coll").WithNamespace(namespace).Request()
+
+	s.Require().NoError(err)
+	s.Equal(namespace, req.GetNamespace())
+}
+
 func (s *QueryIteratorSuite) TestQueryIteratorInit() {
 	ctx := context.Background()
 	s.Run("success", func() {
diff --git a/client/milvusclient/read_option_test.go b/client/milvusclient/read_option_test.go
index 9fd948a634..451f394fc7 100644
--- a/client/milvusclient/read_option_test.go
+++ b/client/milvusclient/read_option_test.go
@@ -90,6 +90,29 @@ func (s *SearchOptionSuite) TestBasic() {
 	s.Error(err)
 }
 
+func (s *SearchOptionSuite) TestWithNamespace() {
+	collName := "namespace_read_option"
+	namespace := "tenant_a"
+
+	searchReq, err := NewSearchOption(collName, 10, []entity.Vector{entity.FloatVector([]float32{0.1, 0.2})}).
+		WithNamespace(namespace).
+		Request()
+	s.Require().NoError(err)
+	s.Equal(namespace, searchReq.GetNamespace())
+
+	queryReq, err := NewQueryOption(collName).
+		WithNamespace(namespace).
+		Request()
+	s.Require().NoError(err)
+	s.Equal(namespace, queryReq.GetNamespace())
+
+	hybridReq, err := NewHybridSearchOption(collName, 10, NewAnnRequest("vector", 10, entity.FloatVector([]float32{0.1, 0.2}))).
+		WithNamespace(namespace).
+		HybridRequest()
+	s.Require().NoError(err)
+	s.Equal(namespace, hybridReq.GetNamespace())
+}
+
 func (s *SearchOptionSuite) TestPlaceHolder() {
 	type testCase struct {
 		tag         string
diff --git a/client/milvusclient/read_options.go b/client/milvusclient/read_options.go
index f0db347caa..96b87c7361 100644
--- a/client/milvusclient/read_options.go
+++ b/client/milvusclient/read_options.go
@@ -59,6 +59,7 @@ type searchOption struct {
 	annRequest                 *AnnRequest
 	collectionName             string
 	partitionNames             []string
+	namespace                  *string
 	outputFields               []string
 	searchAggregation          *SearchAggregation
 	consistencyLevel           entity.ConsistencyLevel
@@ -333,6 +334,7 @@ func (opt *searchOption) Request() (*milvuspb.SearchRequest, error) {
 
 	request.CollectionName = opt.collectionName
 	request.PartitionNames = opt.partitionNames
+	request.Namespace = opt.namespace
 	request.ConsistencyLevel = commonpb.ConsistencyLevel(opt.consistencyLevel)
 	request.UseDefaultConsistency = opt.useDefaultConsistencyLevel
 	request.OutputFields = opt.outputFields
@@ -367,6 +369,11 @@ func (opt *searchOption) WithPartitions(partitionNames ...string) *searchOption
 	return opt
 }
 
+func (opt *searchOption) WithNamespace(namespace string) *searchOption {
+	opt.namespace = &namespace
+	return opt
+}
+
 func (opt *searchOption) WithFilter(expr string) *searchOption {
 	opt.annRequest.WithFilter(expr)
 	return opt
@@ -525,6 +532,7 @@ type HybridSearchOption interface {
 type hybridSearchOption struct {
 	collectionName string
 	partitionNames []string
+	namespace      *string
 
 	reqs []*AnnRequest
 
@@ -554,6 +562,11 @@ func (opt *hybridSearchOption) WithPartitions(partitions ...string) *hybridSearc
 	return opt
 }
 
+func (opt *hybridSearchOption) WithNamespace(namespace string) *hybridSearchOption {
+	opt.namespace = &namespace
+	return opt
+}
+
 func (opt *hybridSearchOption) WithOutputFields(outputFields ...string) *hybridSearchOption {
 	opt.outputFields = outputFields
 	return opt
@@ -596,6 +609,7 @@ func (opt *hybridSearchOption) HybridRequest() (*milvuspb.HybridSearchRequest, e
 	r := &milvuspb.HybridSearchRequest{
 		CollectionName:        opt.collectionName,
 		PartitionNames:        opt.partitionNames,
+		Namespace:             opt.namespace,
 		Requests:              requests,
 		UseDefaultConsistency: opt.useDefaultConsistency,
 		ConsistencyLevel:      commonpb.ConsistencyLevel(opt.consistencyLevel),
@@ -629,6 +643,7 @@ type QueryOption interface {
 type queryOption struct {
 	collectionName             string
 	partitionNames             []string
+	namespace                  *string
 	queryParams                map[string]string
 	outputFields               []string
 	consistencyLevel           entity.ConsistencyLevel
@@ -641,6 +656,7 @@ func (opt *queryOption) Request() (*milvuspb.QueryRequest, error) {
 	req := &milvuspb.QueryRequest{
 		CollectionName: opt.collectionName,
 		PartitionNames: opt.partitionNames,
+		Namespace:      opt.namespace,
 		OutputFields:   opt.outputFields,
 
 		Expr:                  opt.expr,
@@ -703,6 +719,11 @@ func (opt *queryOption) WithPartitions(partitionNames ...string) *queryOption {
 	return opt
 }
 
+func (opt *queryOption) WithNamespace(namespace string) *queryOption {
+	opt.namespace = &namespace
+	return opt
+}
+
 func (opt *queryOption) WithIDs(ids column.Column) *queryOption {
 	opt.expr = pks2Expr(ids)
 	return opt
diff --git a/client/milvusclient/write_option_test.go b/client/milvusclient/write_option_test.go
index 6db7a33b74..a23b9a30e5 100644
--- a/client/milvusclient/write_option_test.go
+++ b/client/milvusclient/write_option_test.go
@@ -195,6 +195,59 @@ func (s *ColumnBasedDataOptionSuite) TestNewStructSubColumnErrors() {
 	}
 }
 
+func (s *ColumnBasedDataOptionSuite) TestWithNamespace() {
+	collName := "namespace_write_option"
+	namespace := "tenant_a"
+	coll := &entity.Collection{
+		Schema: entity.NewSchema().WithName(collName).
+			WithField(entity.NewField().WithName("id").WithDataType(entity.FieldTypeInt64)),
+	}
+
+	insertOpt := NewColumnBasedInsertOption(collName, column.NewColumnInt64("id", []int64{1})).
+		WithNamespace(namespace)
+	insertReq, err := insertOpt.InsertRequest(coll)
+	s.Require().NoError(err)
+	s.Equal(namespace, insertReq.GetNamespace())
+
+	upsertOpt := NewColumnBasedInsertOption(collName, column.NewColumnInt64("id", []int64{1})).
+		WithNamespace(namespace)
+	upsertReq, err := upsertOpt.UpsertRequest(coll)
+	s.Require().NoError(err)
+	s.Equal(namespace, upsertReq.GetNamespace())
+}
+
+func (s *ColumnBasedDataOptionSuite) TestRowBasedWithNamespaceKeepsRows() {
+	collName := "namespace_row_write_option"
+	namespace := "tenant_a"
+	partition := "partition_a"
+	coll := &entity.Collection{
+		Schema: entity.NewSchema().WithName(collName).
+			WithField(entity.NewField().WithName("id").WithDataType(entity.FieldTypeInt64).WithIsPrimaryKey(true)).
+			WithField(entity.NewField().WithName("name").WithDataType(entity.FieldTypeVarChar).WithMaxLength(64)),
+	}
+	rows := []any{map[string]any{"id": int64(1), "name": "alice"}}
+
+	var insertOpt InsertOption = NewRowBasedInsertOption(collName, rows...).
+		WithPartition(partition).
+		WithNamespace(namespace)
+	insertReq, err := insertOpt.InsertRequest(coll)
+	s.Require().NoError(err)
+	s.Equal(partition, insertReq.GetPartitionName())
+	s.Equal(namespace, insertReq.GetNamespace())
+	s.EqualValues(1, insertReq.GetNumRows())
+	s.Len(insertReq.GetFieldsData(), 2)
+
+	var upsertOpt UpsertOption = NewRowBasedInsertOption(collName, rows...).
+		WithPartition(partition).
+		WithNamespace(namespace)
+	upsertReq, err := upsertOpt.UpsertRequest(coll)
+	s.Require().NoError(err)
+	s.Equal(partition, upsertReq.GetPartitionName())
+	s.Equal(namespace, upsertReq.GetNamespace())
+	s.EqualValues(1, upsertReq.GetNumRows())
+	s.Len(upsertReq.GetFieldsData(), 2)
+}
+
 func TestRowBasedDataOption(t *testing.T) {
 	suite.Run(t, new(ColumnBasedDataOptionSuite))
 }
@@ -210,6 +263,14 @@ func (s *DeleteOptionSuite) TestBasic() {
 	s.Equal(collectionName, opt.Request().GetCollectionName())
 }
 
+func (s *DeleteOptionSuite) TestWithNamespace() {
+	collectionName := fmt.Sprintf("coll_%s", s.randString(6))
+	namespace := "tenant_a"
+
+	req := NewDeleteOption(collectionName).WithNamespace(namespace).Request()
+	s.Equal(namespace, req.GetNamespace())
+}
+
 func TestDeleteOption(t *testing.T) {
 	suite.Run(t, new(DeleteOptionSuite))
 }
diff --git a/client/milvusclient/write_options.go b/client/milvusclient/write_options.go
index a7f4dda37c..f45b1af61b 100644
--- a/client/milvusclient/write_options.go
+++ b/client/milvusclient/write_options.go
@@ -51,6 +51,7 @@ var (
 type columnBasedDataOption struct {
 	collName      string
 	partitionName string
+	namespace     *string
 	columns       []column.Column
 	partialUpdate bool
 
@@ -379,6 +380,14 @@ func (opt *columnBasedDataOption) WithPartition(partitionName string) *columnBas
 	return opt
 }
 
+// WithNamespace scopes the write to a collection namespace. Primary keys are
+// still collection-scoped for delete/upsert tombstones, so callers must keep
+// primary keys unique across namespaces in the same collection.
+func (opt *columnBasedDataOption) WithNamespace(namespace string) *columnBasedDataOption {
+	opt.namespace = &namespace
+	return opt
+}
+
 func (opt *columnBasedDataOption) WithPartialUpdate(partialUpdate bool) *columnBasedDataOption {
 	opt.partialUpdate = partialUpdate
 	return opt
@@ -452,6 +461,7 @@ func (opt *columnBasedDataOption) InsertRequest(coll *entity.Collection) (*milvu
 	return &milvuspb.InsertRequest{
 		CollectionName:  opt.collName,
 		PartitionName:   opt.partitionName,
+		Namespace:       opt.namespace,
 		FieldsData:      fieldsData,
 		NumRows:         uint32(rowNum),
 		SchemaTimestamp: coll.UpdateTimestamp,
@@ -477,6 +487,7 @@ func (opt *columnBasedDataOption) UpsertRequest(coll *entity.Collection) (*milvu
 	return &milvuspb.UpsertRequest{
 		CollectionName:  opt.collName,
 		PartitionName:   opt.partitionName,
+		Namespace:       opt.namespace,
 		FieldsData:      fieldsData,
 		NumRows:         uint32(rowNum),
 		SchemaTimestamp: coll.UpdateTimestamp,
@@ -509,6 +520,36 @@ func NewRowBasedInsertOption(collName string, rows ...any) *rowBasedDataOption {
 	}
 }
 
+func (opt *rowBasedDataOption) WithPartition(partitionName string) *rowBasedDataOption {
+	opt.columnBasedDataOption.WithPartition(partitionName)
+	return opt
+}
+
+func (opt *rowBasedDataOption) WithNamespace(namespace string) *rowBasedDataOption {
+	opt.columnBasedDataOption.WithNamespace(namespace)
+	return opt
+}
+
+func (opt *rowBasedDataOption) WithPartialUpdate(partialUpdate bool) *rowBasedDataOption {
+	opt.columnBasedDataOption.WithPartialUpdate(partialUpdate)
+	return opt
+}
+
+func (opt *rowBasedDataOption) WithArrayAppend(fieldName string) *rowBasedDataOption {
+	opt.columnBasedDataOption.WithArrayAppend(fieldName)
+	return opt
+}
+
+func (opt *rowBasedDataOption) WithArrayRemove(fieldName string) *rowBasedDataOption {
+	opt.columnBasedDataOption.WithArrayRemove(fieldName)
+	return opt
+}
+
+func (opt *rowBasedDataOption) WithFieldPartialOp(fieldName string, op schemapb.FieldPartialUpdateOp_OpType) *rowBasedDataOption {
+	opt.columnBasedDataOption.WithFieldPartialOp(fieldName, op)
+	return opt
+}
+
 func (opt *rowBasedDataOption) InsertRequest(coll *entity.Collection) (*milvuspb.InsertRequest, error) {
 	columns, err := row.AnyToColumns(opt.rows, opt.keepAutoIDPk, coll.Schema)
 	if err != nil {
@@ -522,6 +563,7 @@ func (opt *rowBasedDataOption) InsertRequest(coll *entity.Collection) (*milvuspb
 	return &milvuspb.InsertRequest{
 		CollectionName: opt.collName,
 		PartitionName:  opt.partitionName,
+		Namespace:      opt.namespace,
 		FieldsData:     fieldsData,
 		NumRows:        uint32(rowNum),
 	}, nil
@@ -545,6 +587,7 @@ func (opt *rowBasedDataOption) UpsertRequest(coll *entity.Collection) (*milvuspb
 	return &milvuspb.UpsertRequest{
 		CollectionName: opt.collName,
 		PartitionName:  opt.partitionName,
+		Namespace:      opt.namespace,
 		FieldsData:     fieldsData,
 		NumRows:        uint32(rowNum),
 		PartialUpdate:  partialUpdate,
@@ -586,6 +629,7 @@ type DeleteOption interface {
 type deleteOption struct {
 	collectionName string
 	partitionName  string
+	namespace      *string
 	expr           string
 }
 
@@ -593,6 +637,7 @@ func (opt *deleteOption) Request() *milvuspb.DeleteRequest {
 	return &milvuspb.DeleteRequest{
 		CollectionName: opt.collectionName,
 		PartitionName:  opt.partitionName,
+		Namespace:      opt.namespace,
 		Expr:           opt.expr,
 	}
 }
@@ -617,6 +662,14 @@ func (opt *deleteOption) WithPartition(partitionName string) *deleteOption {
 	return opt
 }
 
+// WithNamespace scopes the delete request to a collection namespace. Delete
+// tombstones are primary-key based, so callers must keep primary keys unique
+// across namespaces in the same collection.
+func (opt *deleteOption) WithNamespace(namespace string) *deleteOption {
+	opt.namespace = &namespace
+	return opt
+}
+
 func NewDeleteOption(collectionName string) *deleteOption {
 	return &deleteOption{collectionName: collectionName}
 }
diff --git a/client/milvusclient/write_options_partial_op_test.go b/client/milvusclient/write_options_partial_op_test.go
index 2c6d5a299e..fc91b12511 100644
--- a/client/milvusclient/write_options_partial_op_test.go
+++ b/client/milvusclient/write_options_partial_op_test.go
@@ -153,11 +153,12 @@ func TestRowBasedUpsertEmitsFieldOps(t *testing.T) {
 		map[string]any{"id": int64(1), "tags": []int64{10}},
 		map[string]any{"id": int64(2), "tags": []int64{20, 30}},
 	}
-	opt := NewRowBasedInsertOption(coll.Name, rows...)
-	opt.WithArrayAppend("tags")
+	opt := NewRowBasedInsertOption(coll.Name, rows...).
+		WithArrayAppend("tags")
 
 	req, err := opt.UpsertRequest(coll)
 	require.NoError(t, err)
+	assert.EqualValues(t, len(rows), req.GetNumRows())
 	assert.True(t, req.GetPartialUpdate())
 	tagsOp := findOp(req.GetFieldOps(), "tags")
 	require.NotNil(t, tagsOp)
diff --git a/deployments/docker/dev/docker-compose-apple-silicon.yml b/deployments/docker/dev/docker-compose-apple-silicon.yml
index f0a0f26ff0..1505a7ee25 100644
--- a/deployments/docker/dev/docker-compose-apple-silicon.yml
+++ b/deployments/docker/dev/docker-compose-apple-silicon.yml
@@ -1,5 +1,3 @@
-version: '3.5'
-
 services:
   etcd:
     image: quay.io/coreos/etcd:v3.5.25
@@ -17,7 +15,7 @@ services:
       - "4001:4001"
 
   pulsar:
-    image: milvusdb/pulsar:v2.8.2-m1
+    image: ${PULSAR_IMAGE:-harbor.milvus.io/dockerhub/milvusdb/pulsar:v2.8.2-m1}
     volumes:
       - ${DOCKER_VOLUME_DIRECTORY:-.}/volumes/pulsar:/pulsar/data
     environment:
diff --git a/internal/proxy/impl.go b/internal/proxy/impl.go
index 283718e406..5a937fceb5 100644
--- a/internal/proxy/impl.go
+++ b/internal/proxy/impl.go
@@ -3027,6 +3027,7 @@ func (node *Proxy) search(ctx context.Context, request *milvuspb.SearchRequest,
 		shardClientMgr:         node.shardMgr,
 		enableMaterializedView: node.enableMaterializedView,
 		mustUsePartitionKey:    Params.ProxyCfg.MustUsePartitionKey.GetAsBool(),
+		chMgr:                  node.chMgr,
 	}
 
 	succeeded := false
@@ -3254,6 +3255,7 @@ func (node *Proxy) hybridSearch(ctx context.Context, request *milvuspb.HybridSea
 		lb:                  node.lbPolicy,
 		shardClientMgr:      node.shardMgr,
 		mustUsePartitionKey: Params.ProxyCfg.MustUsePartitionKey.GetAsBool(),
+		chMgr:               node.chMgr,
 	}
 
 	succeeded := false
@@ -3529,6 +3531,7 @@ func (node *Proxy) handleIfSearchByPK(ctx context.Context, request *milvuspb.Sea
 		GuaranteeTimestamp:    request.GuaranteeTimestamp,
 		ConsistencyLevel:      request.ConsistencyLevel,
 		UseDefaultConsistency: request.UseDefaultConsistency,
+		Namespace:             request.Namespace,
 	}
 
 	// Create queryTask to execute the retrieval
@@ -3552,6 +3555,7 @@ func (node *Proxy) handleIfSearchByPK(ctx context.Context, request *milvuspb.Sea
 		mustUsePartitionKey: Params.ProxyCfg.MustUsePartitionKey.GetAsBool(),
 		// reQuery defaults to false - we need full query processing:
 		// partition conversion, struct field reconstruction, timestamp handling etc
+		chMgr: node.chMgr,
 	}
 
 	// Execute query
@@ -3828,6 +3832,7 @@ func (node *Proxy) Query(ctx context.Context, request *milvuspb.QueryRequest) (*
 		lb:                  node.lbPolicy,
 		shardclientMgr:      node.shardMgr,
 		mustUsePartitionKey: Params.ProxyCfg.MustUsePartitionKey.GetAsBool(),
+		chMgr:               node.chMgr,
 	}
 
 	subLabel := GetCollectionRateSubLabel(request)
diff --git a/internal/proxy/impl_test.go b/internal/proxy/impl_test.go
index 371aa60d84..fc9c6887ed 100644
--- a/internal/proxy/impl_test.go
+++ b/internal/proxy/impl_test.go
@@ -31,6 +31,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/mock"
 	"github.com/stretchr/testify/require"
+	"go.opentelemetry.io/otel/trace"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/protobuf/proto"
@@ -46,6 +47,7 @@ import (
 	"github.com/milvus-io/milvus/internal/mocks/distributed/mock_streaming"
 	"github.com/milvus-io/milvus/internal/proxy/shardclient"
 	"github.com/milvus-io/milvus/internal/util/dependency"
+	"github.com/milvus-io/milvus/internal/util/segcore"
 	"github.com/milvus-io/milvus/internal/util/sessionutil"
 	"github.com/milvus-io/milvus/pkg/v3/common"
 	"github.com/milvus-io/milvus/pkg/v3/proto/datapb"
@@ -2207,6 +2209,88 @@ func TestHandleIfSearchByPK_BM25Detection(t *testing.T) {
 	})
 }
 
+func TestHandleIfSearchByPK_PreservesNamespaceInInternalQuery(t *testing.T) {
+	mockey.PatchConvey("TestHandleIfSearchByPK_PreservesNamespaceInInternalQuery", t, func() {
+		paramtable.Init()
+		originalCache := globalMetaCache
+		defer func() { globalMetaCache = originalCache }()
+
+		namespace := "tenant_a"
+		schema := &schemapb.CollectionSchema{
+			Name:            "test_collection",
+			EnableNamespace: true,
+			Fields: []*schemapb.FieldSchema{
+				{FieldID: 100, Name: "id", IsPrimaryKey: true, DataType: schemapb.DataType_Int64},
+				{
+					FieldID:    101,
+					Name:       "vec",
+					DataType:   schemapb.DataType_FloatVector,
+					TypeParams: []*commonpb.KeyValuePair{{Key: "dim", Value: "2"}},
+				},
+			},
+		}
+
+		cache := NewMockCache(t)
+		cache.EXPECT().
+			GetCollectionInfo(mock.Anything, "default", "test_collection", int64(0)).
+			Return(&collectionInfo{schema: newSchemaInfo(schema)}, nil)
+		globalMetaCache = cache
+
+		var capturedNamespace *string
+		mockey.Mock((*Proxy).query).To(func(_ *Proxy, _ context.Context, qt *queryTask, _ trace.Span) (*milvuspb.QueryResults, segcore.StorageCost, error) {
+			capturedNamespace = qt.request.Namespace
+			return &milvuspb.QueryResults{
+				Status: merr.Success(),
+				FieldsData: []*schemapb.FieldData{
+					{
+						FieldName: "id",
+						FieldId:   100,
+						Type:      schemapb.DataType_Int64,
+						Field: &schemapb.FieldData_Scalars{
+							Scalars: &schemapb.ScalarField{
+								Data: &schemapb.ScalarField_LongData{
+									LongData: &schemapb.LongArray{Data: []int64{1}},
+								},
+							},
+						},
+					},
+					{
+						FieldName: "vec",
+						FieldId:   101,
+						Type:      schemapb.DataType_FloatVector,
+						Field: &schemapb.FieldData_Vectors{
+							Vectors: &schemapb.VectorField{
+								Dim: 2,
+								Data: &schemapb.VectorField_FloatVector{
+									FloatVector: &schemapb.FloatArray{Data: []float32{0.1, 0.2}},
+								},
+							},
+						},
+					},
+				},
+			}, segcore.StorageCost{}, nil
+		}).Build()
+
+		node := &Proxy{}
+		req := &milvuspb.SearchRequest{
+			DbName:         "default",
+			CollectionName: "test_collection",
+			Namespace:      &namespace,
+			SearchInput: &milvuspb.SearchRequest_Ids{
+				Ids: &schemapb.IDs{
+					IdField: &schemapb.IDs_IntId{IntId: &schemapb.LongArray{Data: []int64{1}}},
+				},
+			},
+			SearchParams: []*commonpb.KeyValuePair{{Key: AnnsFieldKey, Value: "vec"}},
+		}
+
+		_, err := node.handleIfSearchByPK(context.Background(), req)
+		assert.NoError(t, err)
+		require.NotNil(t, capturedNamespace)
+		assert.Equal(t, namespace, *capturedNamespace)
+	})
+}
+
 func TestProxy_ManualCompaction_ExternalCollection(t *testing.T) {
 	// Save and restore globalMetaCache
 	cache := globalMetaCache
diff --git a/internal/proxy/routing_table_hash_test.go b/internal/proxy/routing_table_hash_test.go
index ff67ae5883..7167486cd7 100644
--- a/internal/proxy/routing_table_hash_test.go
+++ b/internal/proxy/routing_table_hash_test.go
@@ -84,6 +84,8 @@ func TestRepackDeleteMsgByHashPreservesModuloRouting(t *testing.T) {
 		2,
 		"partition",
 		"default",
+		nil,
+		nil,
 	)
 
 	assert.NoError(t, err)
@@ -125,6 +127,8 @@ func TestRepackDeleteMsgByHashReturnsRoutingErrorWithoutChannels(t *testing.T) {
 		2,
 		"partition",
 		"default",
+		nil,
+		nil,
 	)
 
 	assert.ErrorIs(t, err, common.ErrRoutingTableNoValues)
diff --git a/internal/proxy/search_pipeline.go b/internal/proxy/search_pipeline.go
index 4724966c5e..ce075c50c2 100644
--- a/internal/proxy/search_pipeline.go
+++ b/internal/proxy/search_pipeline.go
@@ -1478,6 +1478,7 @@ func (op *requeryOperator) requery(ctx context.Context, span trace.Span, ids *sc
 		preferredNodes: preferredNodes,
 		fastSkip:       true,
 		reQuery:        true,
+		chMgr:          op.node.(*Proxy).chMgr,
 	}
 	queryResult, storageCost, err := op.node.(*Proxy).query(op.traceCtx, qt, span)
 	if err != nil {
diff --git a/internal/proxy/search_util.go b/internal/proxy/search_util.go
index 8455f0ac21..6d8f268c08 100644
--- a/internal/proxy/search_util.go
+++ b/internal/proxy/search_util.go
@@ -1070,6 +1070,7 @@ func convertHybridSearchToSearch(req *milvuspb.HybridSearchRequest) *milvuspb.Se
 		PartitionNames:        req.GetPartitionNames(),
 		OutputFields:          req.GetOutputFields(),
 		SearchParams:          req.GetRankParams(),
+		Namespace:             req.Namespace,
 		TravelTimestamp:       req.GetTravelTimestamp(),
 		GuaranteeTimestamp:    req.GetGuaranteeTimestamp(),
 		Nq:                    0,
@@ -1079,7 +1080,6 @@ func convertHybridSearchToSearch(req *milvuspb.HybridSearchRequest) *milvuspb.Se
 		SearchByPrimaryKeys:   false,
 		SubReqs:               nil,
 		FunctionScore:         req.FunctionScore,
-		Namespace:             req.Namespace,
 	}
 
 	for _, sub := range req.GetRequests() {
diff --git a/internal/proxy/search_util_test.go b/internal/proxy/search_util_test.go
new file mode 100644
index 0000000000..46be16d54e
--- /dev/null
+++ b/internal/proxy/search_util_test.go
@@ -0,0 +1,39 @@
+// Licensed to the LF AI & Data foundation under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package proxy
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/milvus-io/milvus-proto/go-api/v3/milvuspb"
+)
+
+func TestConvertHybridSearchToSearchKeepsNamespace(t *testing.T) {
+	namespace := "tenant_a"
+
+	searchReq := convertHybridSearchToSearch(&milvuspb.HybridSearchRequest{
+		CollectionName: "coll",
+		Namespace:      &namespace,
+		Requests: []*milvuspb.SearchRequest{
+			{Nq: 1},
+		},
+	})
+
+	assert.Equal(t, namespace, searchReq.GetNamespace())
+}
diff --git a/internal/proxy/service_provider.go b/internal/proxy/service_provider.go
index 2370b7f51a..b2f2a31c38 100644
--- a/internal/proxy/service_provider.go
+++ b/internal/proxy/service_provider.go
@@ -208,6 +208,7 @@ func (node *CachedProxyServiceProvider) DescribeCollection(ctx context.Context,
 		}),
 		StructArrayFields:  cloneStructArrayFields(c.schema.StructArrayFields),
 		EnableDynamicField: c.schema.EnableDynamicField,
+		EnableNamespace:    c.schema.EnableNamespace,
 		Properties:         c.schema.Properties,
 		Functions:          c.schema.Functions,
 		DbName:             c.schema.DbName,
diff --git a/internal/proxy/service_provider_test.go b/internal/proxy/service_provider_test.go
index b593567699..7ebb56f758 100644
--- a/internal/proxy/service_provider_test.go
+++ b/internal/proxy/service_provider_test.go
@@ -91,6 +91,7 @@ func TestCachedProxyServiceProvider_DescribeCollection_FilterNamespaceField(t *t
 	schema := &schemapb.CollectionSchema{
 		Name:               collectionName,
 		EnableDynamicField: true,
+		EnableNamespace:    true,
 		Fields: []*schemapb.FieldSchema{
 			{
 				FieldID:      common.StartOfUserFieldID,
@@ -128,6 +129,7 @@ func TestCachedProxyServiceProvider_DescribeCollection_FilterNamespaceField(t *t
 	})
 	assert.NoError(t, err)
 	assert.Equal(t, commonpb.ErrorCode_Success, resp.GetStatus().GetErrorCode())
+	assert.True(t, resp.GetSchema().GetEnableNamespace())
 
 	fieldNames := make(map[string]struct{})
 	for _, f := range resp.GetSchema().GetFields() {
diff --git a/internal/proxy/task_delete.go b/internal/proxy/task_delete.go
index d15bed4c6f..1c527f255c 100644
--- a/internal/proxy/task_delete.go
+++ b/internal/proxy/task_delete.go
@@ -128,7 +128,14 @@ func (dt *deleteTask) getChannels() []pChan {
 }
 
 func (dt *deleteTask) PreExecute(ctx context.Context) error {
-	return nil
+	if dt.req.Namespace == nil {
+		return nil
+	}
+	schema, err := globalMetaCache.GetCollectionSchema(ctx, dt.req.GetDbName(), dt.req.GetCollectionName())
+	if err != nil {
+		return err
+	}
+	return common.CheckNamespace(schema.CollectionSchema, dt.req.Namespace)
 }
 
 func (dt *deleteTask) PostExecute(ctx context.Context) error {
@@ -151,12 +158,30 @@ func repackDeleteMsgByHash(
 	partitionID int64,
 	partitionName string,
 	dbName string,
+	namespace *string,
+	schema *schemapb.CollectionSchema,
 ) (map[uint32][]*msgstream.DeleteMsg, int64, error) {
 	maxSize := Params.PulsarCfg.MaxMessageSize.GetAsInt()
-	hashValues, err := typeutil.HashPK2Channels(primaryKeys, vChannels)
+	var hashValues []uint32
+	// Delete tombstones are PK+timestamp based. Namespace can narrow routing,
+	// but it is not part of the tombstone identity; PKs must stay unique across
+	// namespaces in the same collection.
+	channelID, ok, err := namespaceShardingChannelID(schema, namespace, vChannels)
 	if err != nil {
 		return nil, 0, err
 	}
+	if ok {
+		size := typeutil.GetSizeOfIDs(primaryKeys)
+		hashValues = make([]uint32, size)
+		for i := 0; i < size; i++ {
+			hashValues[i] = channelID
+		}
+	} else {
+		hashValues, err = typeutil.HashPK2Channels(primaryKeys, vChannels)
+		if err != nil {
+			return nil, 0, err
+		}
+	}
 	// repack delete msg by dmChannel
 	result := make(map[uint32][]*msgstream.DeleteMsg)
 	lastMessageSize := map[uint32]int{}
@@ -294,11 +319,11 @@ func (dr *deleteRunner) Init(ctx context.Context) error {
 	if err := validateTextStorageV3Enabled(dr.schema.CollectionSchema); err != nil {
 		return ErrWithLog(log, "TEXT field requires StorageV3", err)
 	}
-	if namespacePartitionModeEnabled(dr.schema.CollectionSchema) {
-		partitionName, _, err := resolveNamespacePartitionName(dr.schema.CollectionSchema, dr.req.Namespace, dr.req.GetPartitionName())
-		if err != nil {
-			return err
-		}
+	partitionName, namespaceAsPartition, err := resolveNamespacePartitionName(dr.schema.CollectionSchema, dr.req.Namespace, dr.req.GetPartitionName())
+	if err != nil {
+		return err
+	}
+	if namespaceAsPartition {
 		dr.req.PartitionName = partitionName
 	}
 
@@ -321,9 +346,22 @@ func (dr *deleteRunner) Init(ctx context.Context) error {
 		return merr.WrapErrAsInputError(merr.WrapErrParameterInvalidMsg("delete plan can't be empty or always true : %s", dr.req.GetExpr()))
 	}
 
+	dr.plan.Namespace = namespaceForPlan(dr.schema.CollectionSchema, dr.req.Namespace)
 	// Set partitionIDs, could be empty if no partition name specified and no partition key
 	partName := dr.req.GetPartitionName()
-	if dr.schema.IsPartitionKeyCollection() {
+	if namespacePartitionKeyMode(dr.schema.CollectionSchema) && dr.req.Namespace != nil {
+		if len(partName) > 0 {
+			return merr.WrapErrParameterInvalidMsg("not support manually specifying the partition names if namespace is used")
+		}
+		hashedPartitionNames, err := assignNamespacePartitionKey(ctx, dr.req.GetDbName(), dr.req.GetCollectionName(), dr.req.Namespace)
+		if err != nil {
+			return err
+		}
+		dr.partitionIDs, err = getPartitionIDs(ctx, dr.req.GetDbName(), dr.req.GetCollectionName(), hashedPartitionNames)
+		if err != nil {
+			return err
+		}
+	} else if dr.schema.IsPartitionKeyCollection() {
 		if len(partName) > 0 {
 			return merr.WrapErrParameterInvalidMsg("not support manually specifying the partition names if partition key mode is used")
 		}
@@ -561,13 +599,28 @@ func (dr *deleteRunner) complexDelete(ctx context.Context, plan *planpb.PlanNode
 		return err
 	}
 
-	err = dr.lb.Execute(ctx, shardclient.CollectionWorkLoad{
-		Db:             dr.req.GetDbName(),
-		CollectionName: dr.req.GetCollectionName(),
-		CollectionID:   dr.collectionID,
-		Nq:             1,
-		Exec:           dr.getStreamingQueryAndDelteFunc(plan),
-	})
+	channelName, useNamespaceChannel, err := namespaceShardingChannel(dr.schema.CollectionSchema, dr.req.Namespace, dr.vChannels)
+	if err != nil {
+		return err
+	}
+	if useNamespaceChannel {
+		err = dr.lb.ExecuteWithRetry(ctx, shardclient.ChannelWorkload{
+			Db:             dr.req.GetDbName(),
+			CollectionName: dr.req.GetCollectionName(),
+			CollectionID:   dr.collectionID,
+			Channel:        channelName,
+			Nq:             1,
+			Exec:           dr.getStreamingQueryAndDelteFunc(plan),
+		})
+	} else {
+		err = dr.lb.Execute(ctx, shardclient.CollectionWorkLoad{
+			Db:             dr.req.GetDbName(),
+			CollectionName: dr.req.GetCollectionName(),
+			CollectionID:   dr.collectionID,
+			Nq:             1,
+			Exec:           dr.getStreamingQueryAndDelteFunc(plan),
+		})
+	}
 	dr.result.DeleteCnt = dr.count.Load()
 	dr.result.Timestamp = dr.sessionTS.Load()
 	if err != nil {
diff --git a/internal/proxy/task_delete_streaming.go b/internal/proxy/task_delete_streaming.go
index 5035d5e7d5..07f8db67a5 100644
--- a/internal/proxy/task_delete_streaming.go
+++ b/internal/proxy/task_delete_streaming.go
@@ -6,6 +6,7 @@ import (
 
 	"go.opentelemetry.io/otel"
 
+	"github.com/milvus-io/milvus-proto/go-api/v3/schemapb"
 	"github.com/milvus-io/milvus/internal/distributed/streaming"
 	"github.com/milvus-io/milvus/internal/util/hookutil"
 	"github.com/milvus-io/milvus/pkg/v3/mlog"
@@ -26,6 +27,17 @@ func (dt *deleteTask) Execute(ctx context.Context) (err error) {
 	}
 
 	dt.tr = timerecord.NewTimeRecorder(fmt.Sprintf("proxy execute delete %d", dt.ID()))
+
+	var collectionSchema *schemapb.CollectionSchema
+	if dt.req.Namespace != nil || hookutil.IsClusterEncryptionEnabled() {
+		schema, err := globalMetaCache.GetCollectionSchema(ctx, dt.req.GetDbName(), dt.req.GetCollectionName())
+		if err != nil {
+			mlog.Warn(ctx, "get collection schema from global meta cache failed", mlog.String("collectionName", dt.req.GetCollectionName()), mlog.Err(err))
+			return err
+		}
+		collectionSchema = schema.CollectionSchema
+	}
+
 	result, numRows, err := repackDeleteMsgByHash(
 		ctx, dt.primaryKeys,
 		dt.vChannels, dt.idAllocator,
@@ -33,6 +45,8 @@ func (dt *deleteTask) Execute(ctx context.Context) (err error) {
 		dt.req.GetCollectionName(),
 		dt.partitionID, dt.req.GetPartitionName(),
 		dt.req.GetDbName(),
+		dt.req.Namespace,
+		collectionSchema,
 	)
 	if err != nil {
 		return err
@@ -40,13 +54,7 @@ func (dt *deleteTask) Execute(ctx context.Context) (err error) {
 
 	var ez *message.CipherConfig
 	if hookutil.IsClusterEncryptionEnabled() {
-		schema, err := globalMetaCache.GetCollectionSchema(ctx, dt.req.GetDbName(), dt.req.GetCollectionName())
-		if err != nil {
-			mlog.Warn(ctx, "get collection schema from global meta cache failed", mlog.String("collectionName", dt.req.GetCollectionName()), mlog.Err(err))
-			return err
-		}
-
-		ez = hookutil.GetEzByCollProperties(schema.GetProperties(), dt.collectionID).AsMessageConfig()
+		ez = hookutil.GetEzByCollProperties(collectionSchema.GetProperties(), dt.collectionID).AsMessageConfig()
 	}
 
 	var msgs []message.MutableMessage
diff --git a/internal/proxy/task_delete_test.go b/internal/proxy/task_delete_test.go
index 1082617474..ee3a88f80e 100644
--- a/internal/proxy/task_delete_test.go
+++ b/internal/proxy/task_delete_test.go
@@ -138,6 +138,19 @@ func TestDeleteTask_GetChannels(t *testing.T) {
 	assert.ElementsMatch(t, channels, dt.pChannels)
 }
 
+func TestDeleteTask_PreExecuteSkipsNamespaceValidationWhenUnset(t *testing.T) {
+	cache := globalMetaCache
+	globalMetaCache = nil
+	defer func() {
+		globalMetaCache = cache
+	}()
+
+	dt := deleteTask{
+		req: &milvuspb.DeleteRequest{},
+	}
+	assert.NoError(t, dt.PreExecute(context.Background()))
+}
+
 func TestDeleteTask_Execute(t *testing.T) {
 	collectionName := "test_delete"
 	collectionID := int64(111)
@@ -334,6 +347,38 @@ func (s *DeleteRunnerSuite) TestInitSuccess() {
 		s.Require().Equal(0, len(dr.partitionIDs))
 	})
 
+	s.Run("namespace assigns partition", func() {
+		mockChMgr := NewMockChannelsMgr(s.T())
+		namespace := "ns-1"
+		partitionNames := []string{"_default_0", "_default_1"}
+		partitionIDs := map[string]int64{"_default_0": 100, "_default_1": 101}
+		schema := namespaceEnabledSchema(
+			&schemapb.FieldSchema{FieldID: common.StartOfUserFieldID, Name: "pk", IsPrimaryKey: true, DataType: schemapb.DataType_Int64},
+			&schemapb.FieldSchema{FieldID: common.StartOfUserFieldID + 1, Name: "non_pk", DataType: schemapb.DataType_Int64},
+		)
+		s.schema = newSchemaInfo(schema)
+		dr := deleteRunner{
+			req: &milvuspb.DeleteRequest{
+				CollectionName: s.collectionName,
+				Expr:           "pk == 1",
+				Namespace:      &namespace,
+			},
+			chMgr: mockChMgr,
+		}
+		s.mockCache.EXPECT().GetDatabaseInfo(mock.Anything, mock.Anything).Return(&databaseInfo{dbID: 0}, nil)
+		s.mockCache.EXPECT().GetCollectionID(mock.Anything, mock.Anything, mock.Anything).Return(s.collectionID, nil)
+		s.mockCache.EXPECT().GetCollectionInfo(mock.Anything, mock.Anything, mock.Anything, mock.Anything).Return(&collectionInfo{}, nil)
+		s.mockCache.EXPECT().GetCollectionSchema(mock.Anything, mock.Anything, mock.Anything).Return(s.schema, nil).Twice()
+		s.mockCache.EXPECT().GetPartitionsIndex(mock.Anything, mock.Anything, mock.Anything).Return(partitionNames, nil)
+		s.mockCache.EXPECT().GetPartitions(mock.Anything, mock.Anything, mock.Anything).Return(partitionIDs, nil)
+		mockChMgr.EXPECT().getVChannels(mock.Anything).Return([]string{"vchan1"}, nil)
+
+		globalMetaCache = s.mockCache
+		s.NoError(dr.Init(context.Background()))
+
+		s.Equal([]int64{expectedNamespacePartitionID(namespace, partitionNames, partitionIDs)}, dr.partitionIDs)
+	})
+
 	s.Run("pk == 1, no partition name", func() {
 		mockChMgr := NewMockChannelsMgr(s.T())
 		dr := deleteRunner{
@@ -471,6 +516,37 @@ func (s *DeleteRunnerSuite) TestInitFailure() {
 		s.Error(dr.Init(context.Background()))
 	})
 
+	s.Run("namespace disabled", func() {
+		mockChMgr := NewMockChannelsMgr(s.T())
+		namespace := "ns-1"
+		dr := deleteRunner{
+			req: &milvuspb.DeleteRequest{
+				CollectionName: s.collectionName,
+				Expr:           "pk == 1",
+				Namespace:      &namespace,
+			},
+			chMgr: mockChMgr,
+		}
+		schema := &schemapb.CollectionSchema{
+			Name: s.collectionName,
+			Fields: []*schemapb.FieldSchema{
+				{
+					FieldID:      common.StartOfUserFieldID,
+					Name:         "pk",
+					IsPrimaryKey: true,
+					DataType:     schemapb.DataType_Int64,
+				},
+			},
+		}
+		s.schema = newSchemaInfo(schema)
+		s.mockCache.EXPECT().GetDatabaseInfo(mock.Anything, mock.Anything).Return(&databaseInfo{dbID: 0}, nil)
+		s.mockCache.EXPECT().GetCollectionID(mock.Anything, mock.Anything, mock.Anything).Return(s.collectionID, nil)
+		s.mockCache.EXPECT().GetCollectionSchema(mock.Anything, mock.Anything, mock.Anything).Return(s.schema, nil)
+
+		globalMetaCache = s.mockCache
+		s.Error(dr.Init(context.Background()))
+	})
+
 	s.Run("fail to get database info", func() {
 		dr := deleteRunner{
 			req: &milvuspb.DeleteRequest{
diff --git a/internal/proxy/task_insert_streaming.go b/internal/proxy/task_insert_streaming.go
index 48465d3989..045ab7c127 100644
--- a/internal/proxy/task_insert_streaming.go
+++ b/internal/proxy/task_insert_streaming.go
@@ -65,7 +65,7 @@ func (it *insertTask) Execute(ctx context.Context) error {
 	if it.partitionKeys == nil {
 		msgs, err = repackInsertDataForStreamingService(it.TraceCtx(), channelNames, it.insertMsg, it.result, ez, it.schemaVersion)
 	} else {
-		msgs, err = repackInsertDataWithPartitionKeyForStreamingService(it.TraceCtx(), channelNames, it.insertMsg, it.result, it.partitionKeys, ez, it.schemaVersion)
+		msgs, err = repackInsertDataWithPartitionKeyForStreamingService(it.TraceCtx(), channelNames, it.insertMsg, it.result, it.partitionKeys, ez, it.schema, it.schemaVersion)
 	}
 	if err != nil {
 		mlog.Warn(ctx, "assign segmentID and repack insert data failed", mlog.Err(err))
@@ -146,11 +146,18 @@ func repackInsertDataWithPartitionKeyForStreamingService(
 	result *milvuspb.MutationResult,
 	partitionKeys *schemapb.FieldData,
 	ez *message.CipherConfig,
+	schema *schemapb.CollectionSchema,
 	schemaVersion int32,
 ) ([]message.MutableMessage, error) {
 	messages := make([]message.MutableMessage, 0)
 
-	channel2RowOffsets, err := assignChannelsByPK(result.IDs, channelNames, insertMsg)
+	var channel2RowOffsets map[string][]int
+	var err error
+	if namespacePartitionKeyModeEnabled(schema) && insertMsg.Namespace != nil {
+		channel2RowOffsets, err = assignChannelsByNamespace(*insertMsg.Namespace, channelNames, insertMsg)
+	} else {
+		channel2RowOffsets, err = assignChannelsByPK(result.IDs, channelNames, insertMsg)
+	}
 	if err != nil {
 		return nil, err
 	}
diff --git a/internal/proxy/task_query.go b/internal/proxy/task_query.go
index d72742621f..2e79e49f39 100644
--- a/internal/proxy/task_query.go
+++ b/internal/proxy/task_query.go
@@ -87,6 +87,7 @@ type queryTask struct {
 	resolvedTimezoneStr  string
 	storageCost          segcore.StorageCost
 	aggregationFieldMap  *agg.AggregationFieldMap
+	chMgr                channelsMgr
 }
 
 func (t *queryTask) getQueryLabel() string {
@@ -805,7 +806,14 @@ func (t *queryTask) PreExecute(ctx context.Context) error {
 	// convert partition names only when requery is false
 	if !t.reQuery {
 		partitionNames := t.request.GetPartitionNames()
-		if t.partitionKeyMode {
+		if namespacePartitionKeyMode(t.schema.CollectionSchema) && t.request.Namespace != nil {
+			hashedPartitionNames, err := assignNamespacePartitionKey(ctx, t.request.GetDbName(), t.request.CollectionName, t.request.Namespace)
+			if err != nil {
+				return err
+			}
+
+			partitionNames = append(partitionNames, hashedPartitionNames...)
+		} else if t.partitionKeyMode {
 			expr, err := exprutil.ParseExprFromPlan(t.plan)
 			if err != nil {
 				return err
@@ -919,6 +927,34 @@ func (t *queryTask) Execute(ctx context.Context) error {
 		mlog.String("requestType", t.getQueryLabel()))
 
 	t.resultBuf = typeutil.NewConcurrentSet[*internalpb.RetrieveResults]()
+	if namespacePartitionKeyModeEnabled(t.schema.CollectionSchema) && t.request.Namespace != nil {
+		channelNames, err := t.chMgr.getVChannels(t.CollectionID)
+		if err != nil {
+			log.Warn(ctx, "get vChannels failed", mlog.Int64("collectionID", t.CollectionID), mlog.Err(err))
+			return err
+		}
+		channelName, ok, err := namespaceShardingChannel(t.schema.CollectionSchema, t.request.Namespace, channelNames)
+		if err != nil {
+			return err
+		}
+		if ok {
+			if err := t.lb.ExecuteWithRetry(ctx, shardclient.ChannelWorkload{
+				Db:              t.request.GetDbName(),
+				CollectionName:  t.collectionName,
+				CollectionID:    t.CollectionID,
+				Channel:         channelName,
+				Nq:              1,
+				Exec:            t.queryShard,
+				PreferredNodeID: preferredNodeForChannel(t.preferredNodes, channelName),
+			}); err != nil {
+				log.Warn(ctx, "fail to execute query", mlog.Err(err))
+				return errors.Wrap(err, "failed to query")
+			}
+
+			log.Debug(ctx, "Query Execute done.")
+			return nil
+		}
+	}
 	err := t.lb.Execute(ctx, shardclient.CollectionWorkLoad{
 		Db:             t.request.GetDbName(),
 		CollectionID:   t.CollectionID,
diff --git a/internal/proxy/task_query_namespace_test.go b/internal/proxy/task_query_namespace_test.go
index 1cae91f54b..f0b6910bbd 100644
--- a/internal/proxy/task_query_namespace_test.go
+++ b/internal/proxy/task_query_namespace_test.go
@@ -11,11 +11,46 @@ import (
 	"github.com/milvus-io/milvus-proto/go-api/v3/milvuspb"
 	"github.com/milvus-io/milvus-proto/go-api/v3/schemapb"
 	"github.com/milvus-io/milvus/internal/parser/planparserv2"
+	"github.com/milvus-io/milvus/pkg/v3/common"
 	"github.com/milvus-io/milvus/pkg/v3/proto/internalpb"
 	"github.com/milvus-io/milvus/pkg/v3/proto/planpb"
 	"github.com/milvus-io/milvus/pkg/v3/util/merr"
+	"github.com/milvus-io/milvus/pkg/v3/util/typeutil"
 )
 
+func namespaceEnabledSchema(fields ...*schemapb.FieldSchema) *schemapb.CollectionSchema {
+	return &schemapb.CollectionSchema{
+		Name: "test_collection",
+		Fields: append(fields, &schemapb.FieldSchema{
+			FieldID:        999,
+			Name:           common.NamespaceFieldName,
+			IsPartitionKey: true,
+			DataType:       schemapb.DataType_VarChar,
+		}),
+		EnableNamespace: true,
+	}
+}
+
+func nonPartitionKeyPredicate(fieldID int64, dataType schemapb.DataType) *planpb.Expr {
+	return &planpb.Expr{
+		Expr: &planpb.Expr_UnaryRangeExpr{
+			UnaryRangeExpr: &planpb.UnaryRangeExpr{
+				ColumnInfo: &planpb.ColumnInfo{
+					FieldId:  fieldID,
+					DataType: dataType,
+				},
+				Op:    planpb.OpType_GreaterThan,
+				Value: &planpb.GenericValue{Val: &planpb.GenericValue_Int64Val{Int64Val: 0}},
+			},
+		},
+	}
+}
+
+func expectedNamespacePartitionID(namespace string, partitionNames []string, partitionIDs map[string]int64) int64 {
+	idx := typeutil.HashString2Uint32(namespace) % uint32(len(partitionNames))
+	return partitionIDs[partitionNames[idx]]
+}
+
 func TestQueryTask_PlanNamespace_AfterPreExecute(t *testing.T) {
 	mockey.PatchConvey("TestQueryTask_PlanNamespace_AfterPreExecute", t, func() {
 		// Setup global meta cache and common mocks
@@ -77,3 +112,53 @@ func TestQueryTask_PlanNamespace_AfterPreExecute(t *testing.T) {
 		assert.Equal(t, *task.request.Namespace, *capturedPlan.Namespace)
 	})
 }
+
+func TestQueryTask_NamespaceSetsPartitionIDs(t *testing.T) {
+	mockey.PatchConvey("TestQueryTask_NamespaceSetsPartitionIDs", t, func() {
+		globalMetaCache = &MetaCache{}
+
+		partitionNames := []string{"_default_0", "_default_1"}
+		partitionIDs := map[string]int64{"_default_0": 101, "_default_1": 102}
+		namespaces := []string{"ns-0", "ns-1", "ns-2", "ns-3", "ns-4", "ns-5", "ns-6", "ns-7"}
+		schema := namespaceEnabledSchema(
+			&schemapb.FieldSchema{FieldID: 100, Name: "id", IsPrimaryKey: true, DataType: schemapb.DataType_Int64},
+			&schemapb.FieldSchema{FieldID: 101, Name: "value", DataType: schemapb.DataType_Int64},
+		)
+
+		mockey.Mock((*MetaCache).GetCollectionID).Return(int64(1001), nil).Build()
+		mockey.Mock((*MetaCache).GetCollectionInfo).Return(&collectionInfo{updateTimestamp: 12345, consistencyLevel: commonpb.ConsistencyLevel_Strong}, nil).Build()
+		mockey.Mock((*MetaCache).GetCollectionSchema).Return(newSchemaInfo(schema), nil).Build()
+		mockey.Mock((*MetaCache).GetPartitionsIndex).Return(partitionNames, nil).Build()
+		mockey.Mock((*MetaCache).GetPartitions).Return(partitionIDs, nil).Build()
+		mockey.Mock(validatePartitionTag).Return(nil).Build()
+		mockey.Mock(isIgnoreGrowing).Return(false, nil).Build()
+
+		mockey.Mock((*queryTask).createPlanArgs).To(func(q *queryTask, ctx context.Context, visitorArgs *planparserv2.ParserVisitorArgs) error {
+			q.plan = &planpb.PlanNode{
+				Node: &planpb.PlanNode_Query{
+					Query: &planpb.QueryPlanNode{
+						Predicates: nonPartitionKeyPredicate(101, schemapb.DataType_Int64),
+					},
+				},
+			}
+			q.translatedOutputFields = []string{"id"}
+			q.userOutputFields = []string{"id"}
+			return nil
+		}).Build()
+
+		for _, ns := range namespaces {
+			namespace := ns
+			task := &queryTask{
+				Condition:       NewTaskCondition(context.Background()),
+				RetrieveRequest: &internalpb.RetrieveRequest{QueryLabel: "query", Base: &commonpb.MsgBase{MsgType: commonpb.MsgType_Retrieve}},
+				ctx:             context.Background(),
+				request:         &milvuspb.QueryRequest{CollectionName: "test_collection", Expr: "value > 0", Namespace: &namespace},
+				result:          &milvuspb.QueryResults{Status: merr.Success()},
+			}
+
+			err := task.PreExecute(context.Background())
+			assert.NoError(t, err)
+			assert.Equal(t, []int64{expectedNamespacePartitionID(namespace, partitionNames, partitionIDs)}, task.GetPartitionIDs())
+		}
+	})
+}
diff --git a/internal/proxy/task_search.go b/internal/proxy/task_search.go
index 7092e7791e..a94af0e237 100644
--- a/internal/proxy/task_search.go
+++ b/internal/proxy/task_search.go
@@ -125,6 +125,8 @@ type searchTask struct {
 
 	hybridSubSearchInfos []hybridSubSearchInfo
 	hybridElementLevel   bool
+
+	chMgr channelsMgr
 }
 
 func (t *searchTask) CanSkipAllocTimestamp() bool {
@@ -1179,6 +1181,23 @@ func (t *searchTask) tryGeneratePlan(params []*commonpb.KeyValuePair, dsl string
 }
 
 func (t *searchTask) tryParsePartitionIDsFromPlan(plan *planpb.PlanNode) ([]int64, error) {
+	if namespacePartitionKeyMode(t.schema.CollectionSchema) && t.request.Namespace != nil {
+		hashedPartitionNames, err := assignNamespacePartitionKey(t.ctx, t.request.GetDbName(), t.collectionName, t.request.Namespace)
+		if err != nil {
+			mlog.Warn(t.ctx, "failed to assign namespace partition key", mlog.Err(err))
+			return nil, err
+		}
+		if len(hashedPartitionNames) > 0 {
+			PartitionIDs, err2 := getPartitionIDs(t.ctx, t.request.GetDbName(), t.collectionName, hashedPartitionNames)
+			if err2 != nil {
+				mlog.Warn(t.ctx, "failed to get namespace partition ids", mlog.Err(err2))
+				return nil, err2
+			}
+			return PartitionIDs, nil
+		}
+		return nil, nil
+	}
+
 	expr, err := exprutil.ParseExprFromPlan(plan)
 	if err != nil {
 		mlog.Warn(t.ctx, "failed to parse expr", mlog.Err(err))
@@ -1212,6 +1231,36 @@ func (t *searchTask) Execute(ctx context.Context) error {
 	defer tr.CtxElapse(ctx, "done")
 
 	t.queryChannelsNode = typeutil.NewConcurrentMap[string, int64]()
+	if namespacePartitionKeyModeEnabled(t.schema.CollectionSchema) && t.request.Namespace != nil {
+		channelNames, err := t.chMgr.getVChannels(t.CollectionID)
+		if err != nil {
+			log.Warn(ctx, "get vChannels failed", mlog.Int64("collectionID", t.CollectionID), mlog.Err(err))
+			return err
+		}
+		channelName, ok, err := namespaceShardingChannel(t.schema.CollectionSchema, t.request.Namespace, channelNames)
+		if err != nil {
+			return err
+		}
+		if ok {
+			if err := t.lb.ExecuteWithRetry(ctx, shardclient.ChannelWorkload{
+				Db:              t.request.GetDbName(),
+				CollectionName:  t.collectionName,
+				CollectionID:    t.CollectionID,
+				Channel:         channelName,
+				Nq:              t.Nq,
+				Exec:            t.searchShard,
+				PreferredNodeID: preferredNodeFromConcurrentMap(t.queryChannelsNode, channelName),
+			}); err != nil {
+				log.Warn(ctx, "search execute failed", mlog.Err(err))
+				return errors.Wrap(err, "failed to search")
+			}
+
+			log.Debug(ctx, "Search Execute done.",
+				mlog.Int64("collection", t.GetCollectionID()),
+				mlog.Int64s("partitionIDs", t.GetPartitionIDs()))
+			return nil
+		}
+	}
 	err := t.lb.Execute(ctx, shardclient.CollectionWorkLoad{
 		Db:             t.request.GetDbName(),
 		CollectionID:   t.CollectionID,
diff --git a/internal/proxy/task_search_namespace_test.go b/internal/proxy/task_search_namespace_test.go
index b1fd575ce4..76c6b3b927 100644
--- a/internal/proxy/task_search_namespace_test.go
+++ b/internal/proxy/task_search_namespace_test.go
@@ -70,6 +70,55 @@ func TestSearchTask_PlanNamespace_AfterPreExecute(t *testing.T) {
 	})
 }
 
+func TestSearchTask_NamespaceSetsPartitionIDs(t *testing.T) {
+	mockey.PatchConvey("TestSearchTask_NamespaceSetsPartitionIDs", t, func() {
+		globalMetaCache = &MetaCache{}
+
+		partitionNames := []string{"_default_0", "_default_1"}
+		partitionIDs := map[string]int64{"_default_0": 101, "_default_1": 102}
+		namespaces := []string{"ns-0", "ns-1", "ns-2", "ns-3", "ns-4", "ns-5", "ns-6", "ns-7"}
+		schema := namespaceEnabledSchema(
+			&schemapb.FieldSchema{FieldID: 100, Name: "id", IsPrimaryKey: true, DataType: schemapb.DataType_Int64},
+			&schemapb.FieldSchema{FieldID: 101, Name: "vec", DataType: schemapb.DataType_FloatVector, TypeParams: []*commonpb.KeyValuePair{{Key: "dim", Value: "4"}}},
+			&schemapb.FieldSchema{FieldID: 102, Name: "value", DataType: schemapb.DataType_Int64},
+		)
+
+		mockey.Mock((*MetaCache).GetCollectionID).Return(int64(1001), nil).Build()
+		mockey.Mock((*MetaCache).GetCollectionInfo).Return(&collectionInfo{updateTimestamp: 12345, consistencyLevel: commonpb.ConsistencyLevel_Strong}, nil).Build()
+		mockey.Mock((*MetaCache).GetCollectionSchema).Return(newSchemaInfo(schema), nil).Build()
+		mockey.Mock((*MetaCache).GetPartitionsIndex).Return(partitionNames, nil).Build()
+		mockey.Mock((*MetaCache).GetPartitions).Return(partitionIDs, nil).Build()
+		mockey.Mock(isIgnoreGrowing).Return(false, nil).Build()
+		mockey.Mock((*searchTask).checkNq).Return(int64(1), nil).Build()
+		mockey.Mock((*searchTask).tryGeneratePlan).To(func(_ *searchTask, _ []*commonpb.KeyValuePair, _ string, _ map[string]*schemapb.TemplateValue) (*planpb.PlanNode, *planpb.QueryInfo, int64, bool, []OrderByField, internalpb.SearchType, error) {
+			plan := &planpb.PlanNode{
+				Node: &planpb.PlanNode_VectorAnns{
+					VectorAnns: &planpb.VectorANNS{
+						Predicates: nonPartitionKeyPredicate(102, schemapb.DataType_Int64),
+					},
+				},
+			}
+			qi := &planpb.QueryInfo{Topk: 10, MetricType: "L2", QueryFieldId: 101, GroupByFieldId: -1}
+			return plan, qi, 0, false, nil, internalpb.SearchType_DEFAULT, nil
+		}).Build()
+
+		for _, ns := range namespaces {
+			namespace := ns
+			task := &searchTask{
+				Condition:     NewTaskCondition(context.Background()),
+				SearchRequest: &internalpb.SearchRequest{Base: &commonpb.MsgBase{MsgType: commonpb.MsgType_Search}},
+				ctx:           context.Background(),
+				request:       &milvuspb.SearchRequest{CollectionName: "test_collection", Namespace: &namespace},
+				result:        &milvuspb.SearchResults{Status: merr.Success()},
+			}
+
+			err := task.PreExecute(context.Background())
+			assert.NoError(t, err)
+			assert.Equal(t, []int64{expectedNamespacePartitionID(namespace, partitionNames, partitionIDs)}, task.GetPartitionIDs())
+		}
+	})
+}
+
 func TestSearchTask_RequeryPlanNamespace(t *testing.T) {
 	mockey.PatchConvey("TestSearchTask_RequeryPlanNamespace", t, func() {
 		// Minimal searchTask with schema and namespace
diff --git a/internal/proxy/task_upsert.go b/internal/proxy/task_upsert.go
index f42837384c..8ac0c64218 100644
--- a/internal/proxy/task_upsert.go
+++ b/internal/proxy/task_upsert.go
@@ -222,6 +222,7 @@ func retrieveByPKs(ctx context.Context, t *upsertTask, ids *schemapb.IDs, output
 		mixCoord:       t.node.(*Proxy).mixCoord,
 		lb:             t.node.(*Proxy).lbPolicy,
 		shardclientMgr: t.node.(*Proxy).shardMgr,
+		chMgr:          t.node.(*Proxy).chMgr,
 	}
 
 	ctx, sp := otel.Tracer(typeutil.ProxyRole).Start(ctx, "Proxy-Upsert-retrieveByPKs")
diff --git a/internal/proxy/task_upsert_streaming.go b/internal/proxy/task_upsert_streaming.go
index a07f892eea..5e21fd785e 100644
--- a/internal/proxy/task_upsert_streaming.go
+++ b/internal/proxy/task_upsert_streaming.go
@@ -88,7 +88,7 @@ func (ut *upsertTask) packInsertMessage(ctx context.Context, ez *message.CipherC
 	if ut.partitionKeys == nil {
 		msgs, err = repackInsertDataForStreamingService(ut.TraceCtx(), channelNames, ut.upsertMsg.InsertMsg, ut.result, ez, ut.schemaVersion)
 	} else {
-		msgs, err = repackInsertDataWithPartitionKeyForStreamingService(ut.TraceCtx(), channelNames, ut.upsertMsg.InsertMsg, ut.result, ut.partitionKeys, ez, ut.schemaVersion)
+		msgs, err = repackInsertDataWithPartitionKeyForStreamingService(ut.TraceCtx(), channelNames, ut.upsertMsg.InsertMsg, ut.result, ut.partitionKeys, ez, ut.schema.CollectionSchema, ut.schemaVersion)
 	}
 	if err != nil {
 		log.Warn(ctx, "assign segmentID and repack insert data failed", mlog.Err(err))
@@ -122,6 +122,8 @@ func (ut *upsertTask) packDeleteMessage(ctx context.Context, ez *message.CipherC
 		ut.upsertMsg.DeleteMsg.CollectionID, ut.upsertMsg.DeleteMsg.CollectionName,
 		ut.upsertMsg.DeleteMsg.PartitionID, ut.upsertMsg.DeleteMsg.PartitionName,
 		ut.req.GetDbName(),
+		ut.req.Namespace,
+		ut.schema.CollectionSchema,
 	)
 	if err != nil {
 		return nil, err
diff --git a/internal/proxy/util.go b/internal/proxy/util.go
index 022fc5414a..bcb545a922 100644
--- a/internal/proxy/util.go
+++ b/internal/proxy/util.go
@@ -2648,6 +2648,30 @@ func assignChannelsByPK(pks *schemapb.IDs, channelNames []string, insertMsg *msg
 	return channel2RowOffsets, nil
 }
 
+func assignChannelsByNamespace(namespace string, channelNames []string, insertMsg *msgstream.InsertMsg) (map[string][]int, error) {
+	if len(channelNames) == 0 {
+		return nil, merr.WrapErrServiceInternalMsg("no virtual channels available for namespace sharding")
+	}
+	channelID := typeutil.HashNamespace2Channels(namespace, channelNames)
+	return assignChannelsByChannel(channelID, channelNames, insertMsg), nil
+}
+
+func assignChannelsByChannel(channelID uint32, channelNames []string, insertMsg *msgstream.InsertMsg) map[string][]int {
+	insertMsg.HashValues = make([]uint32, insertMsg.NumRows)
+	for i := range insertMsg.HashValues {
+		insertMsg.HashValues[i] = channelID
+	}
+
+	channelName := channelNames[channelID]
+	channel2RowOffsets := map[string][]int{
+		channelName: make([]int, 0, insertMsg.NRows()),
+	}
+	for i := range insertMsg.HashValues {
+		channel2RowOffsets[channelName] = append(channel2RowOffsets[channelName], i)
+	}
+	return channel2RowOffsets
+}
+
 func assignPartitionKeys(ctx context.Context, dbName string, collName string, keys []*planpb.GenericValue) ([]string, error) {
 	partitionNames, err := globalMetaCache.GetPartitionsIndex(ctx, dbName, collName)
 	if err != nil {
@@ -2668,6 +2692,16 @@ func assignPartitionKeys(ctx context.Context, dbName string, collName string, ke
 	return hashedPartitionNames, err
 }
 
+func assignNamespacePartitionKey(ctx context.Context, dbName string, collName string, namespace *string) ([]string, error) {
+	if namespace == nil {
+		return nil, nil
+	}
+
+	return assignPartitionKeys(ctx, dbName, collName, []*planpb.GenericValue{
+		{Val: &planpb.GenericValue_StringVal{StringVal: *namespace}},
+	})
+}
+
 func ErrWithLog(logger *mlog.Logger, msg string, err error) error {
 	wrapErr := errors.Wrap(err, msg)
 	if logger != nil {
@@ -2745,8 +2779,64 @@ func checkDynamicFieldDataForPartialUpdate(schema *schemapb.CollectionSchema, in
 	return doCheckDynamicFieldData(schema, insertMsg, true)
 }
 
+func namespaceShardingEnabled(schema *schemapb.CollectionSchema) bool {
+	if schema == nil || !schema.GetEnableNamespace() {
+		return false
+	}
+	enabled, err := common.IsNamespaceShardingEnabled(schema.GetProperties()...)
+	return err == nil && enabled
+}
+
+func namespacePartitionKeyMode(schema *schemapb.CollectionSchema) bool {
+	return schema != nil && schema.GetEnableNamespace() && common.IsNamespaceModePartitionKey(schema.GetProperties()...)
+}
+
+func namespacePartitionKeyModeEnabled(schema *schemapb.CollectionSchema) bool {
+	return namespaceShardingEnabled(schema) && namespacePartitionKeyMode(schema)
+}
+
 func namespacePartitionModeEnabled(schema *schemapb.CollectionSchema) bool {
-	return schema.GetEnableNamespace() && common.IsNamespaceModePartition(schema.GetProperties()...)
+	return schema != nil && schema.GetEnableNamespace() && common.IsNamespaceModePartition(schema.GetProperties()...)
+}
+
+func namespaceShardingChannelID(schema *schemapb.CollectionSchema, namespace *string, channelNames []string) (uint32, bool, error) {
+	if namespace == nil || !namespacePartitionKeyModeEnabled(schema) {
+		return 0, false, nil
+	}
+	if len(channelNames) == 0 {
+		return 0, false, merr.WrapErrServiceInternalMsg("no virtual channels available for namespace sharding")
+	}
+	return typeutil.HashNamespace2Channels(*namespace, channelNames), true, nil
+}
+
+func namespaceShardingChannel(schema *schemapb.CollectionSchema, namespace *string, channelNames []string) (string, bool, error) {
+	channelID, ok, err := namespaceShardingChannelID(schema, namespace, channelNames)
+	if !ok || err != nil {
+		return "", ok, err
+	}
+	return channelNames[channelID], true, nil
+}
+
+func preferredNodeForChannel(preferredNodes map[string]int64, channel string) int64 {
+	if preferredNodes == nil {
+		return 0
+	}
+	preferredNodeID, ok := preferredNodes[channel]
+	if !ok {
+		return 0
+	}
+	return preferredNodeID
+}
+
+func preferredNodeFromConcurrentMap(preferredNodes *typeutil.ConcurrentMap[string, int64], channel string) int64 {
+	if preferredNodes == nil {
+		return 0
+	}
+	preferredNodeID, ok := preferredNodes.Get(channel)
+	if !ok {
+		return 0
+	}
+	return preferredNodeID
 }
 
 func resolveNamespacePartitionName(schema *schemapb.CollectionSchema, namespace *string, partitionName string) (string, bool, error) {
diff --git a/pkg/util/typeutil/hash.go b/pkg/util/typeutil/hash.go
index 104d401095..20b58f18e1 100644
--- a/pkg/util/typeutil/hash.go
+++ b/pkg/util/typeutil/hash.go
@@ -187,3 +187,9 @@ func RearrangePartitionsForPartitionKey(partitions map[string]int64) ([]string,
 
 	return partitionNames, partitionIDs, nil
 }
+
+func HashNamespace2Channels(namespace string, shardNames []string) uint32 {
+	numShard := uint32(len(shardNames))
+	hashValue := HashString2Uint32(namespace)
+	return hashValue % numShard
+}
diff --git a/scripts/stop.sh b/scripts/stop.sh
index d697fe03b7..b7127d6914 100755
--- a/scripts/stop.sh
+++ b/scripts/stop.sh
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+
 # Licensed to the LF AI & Data foundation under one
 # or more contributor license agreements. See the NOTICE file
 # distributed with this work for additional information
@@ -14,12 +16,34 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-echo "Stopping milvus..."
-PROCESS=$(ps -e | grep milvus | grep -v grep | awk '{print $1}')
-if [ -z "$PROCESS" ]; then
-  echo "No milvus process"
-  exit 0
-fi
-kill -15 $PROCESS
-echo "Milvus stopped"
+function filter_milvus_process() {
+  awk '
+    {
+      pid = $1
+      $1 = ""
+      sub(/^[[:space:]]+/, "", $0)
+      # Match Milvus commands, not tools/editors that mention the repo name.
+      if ($0 ~ /^([^[:space:]]*\/)?milvus[[:space:]]+run[[:space:]]/) {
+        print pid
+      }
+    }'
+}
 
+function get_milvus_process() {
+  ps -e -o pid= -o args= | filter_milvus_process
+}
+
+function main() {
+  echo "Stopping milvus..."
+  PROCESS=$(get_milvus_process)
+  if [ -z "$PROCESS" ]; then
+    echo "No milvus process"
+    exit 0
+  fi
+  kill -15 $PROCESS
+  echo "Milvus stopped"
+}
+
+if [[ "${BASH_SOURCE[0]}" == "$0" ]]; then
+  main "$@"
+fi
diff --git a/tests/python_client/milvus_client/test_milvus_client_query.py b/tests/python_client/milvus_client/test_milvus_client_query.py
index e984210570..b154216cf6 100644
--- a/tests/python_client/milvus_client/test_milvus_client_query.py
+++ b/tests/python_client/milvus_client/test_milvus_client_query.py
@@ -805,6 +805,68 @@ class TestMilvusClientQueryValid(TestMilvusClientV2Base):
         )
         self.drop_collection(client, collection_name)
 
+    @pytest.mark.tags(CaseLabel.L1)
+    def test_milvus_client_query_with_multiple_namespaces(self):
+        """
+        target: test query with namespace enabled
+        method: create namespace-enabled collection with multiple shards, insert rows into multiple namespaces, then query by namespace
+        expected: query only returns rows from the requested namespace
+        """
+        client = self._client()
+        collection_name = cf.gen_collection_name_by_testcase_name()
+        shards_num = 4
+        self.create_collection(
+            client,
+            collection_name,
+            default_dim,
+            consistency_level="Strong",
+            enable_namespace=True,
+            shards_num=shards_num,
+        )
+
+        desc = self.describe_collection(client, collection_name)[0]
+        assert desc["enable_namespace"] is True
+        assert desc["num_shards"] == shards_num
+
+        rng = np.random.default_rng(seed=19530)
+        namespaces = [f"namespace_{i}" for i in range(8)]
+        nb_per_namespace = 10
+        ids_by_namespace = {
+            namespace: [idx * 1000 + i for i in range(nb_per_namespace)]
+            for idx, namespace in enumerate(namespaces)
+        }
+        for namespace, ids in ids_by_namespace.items():
+            rows = [
+                {
+                    default_primary_key_field_name: pk,
+                    default_vector_field_name: list(rng.random((1, default_dim))[0]),
+                }
+                for pk in ids
+            ]
+            self.insert(client, collection_name, rows, namespace=namespace)
+
+        for namespace, expected_ids in ids_by_namespace.items():
+            res = self.query(
+                client,
+                collection_name,
+                filter=default_search_exp,
+                output_fields=[default_primary_key_field_name],
+                namespace=namespace,
+            )[0]
+            assert {r[default_primary_key_field_name] for r in res} == set(expected_ids)
+
+        first_id_per_namespace = [ids[0] for ids in ids_by_namespace.values()]
+        for namespace, expected_ids in ids_by_namespace.items():
+            filtered = self.query(
+                client,
+                collection_name,
+                filter=f"{default_primary_key_field_name} in {first_id_per_namespace}",
+                output_fields=[default_primary_key_field_name],
+                namespace=namespace,
+            )[0]
+            assert {r[default_primary_key_field_name] for r in filtered} == {expected_ids[0]}
+        self.drop_collection(client, collection_name)
+
     @pytest.mark.tags(CaseLabel.L1)
     def test_milvus_client_query_output_fields(self):
         """