diff --git a/client/column/columns_test.go b/client/column/columns_test.go
index 1a4b3f1605bf5..bba30794bd446 100644
--- a/client/column/columns_test.go
+++ b/client/column/columns_test.go
@@ -40,9 +40,9 @@ func TestIDColumns(t *testing.T) {
 
 	t.Run("nil id", func(t *testing.T) {
 		_, err := IDColumns(intPKCol, nil, 0, -1)
-		assert.Error(t, err)
+		assert.NoError(t, err)
 		_, err = IDColumns(strPKCol, nil, 0, -1)
-		assert.Error(t, err)
+		assert.NoError(t, err)
 
 		idField := &schemapb.IDs{}
 		col, err := IDColumns(intPKCol, idField, 0, -1)
diff --git a/client/example/database/main.go b/client/example/database/main.go
deleted file mode 100644
index 0069923d9a2c6..0000000000000
--- a/client/example/database/main.go
+++ /dev/null
@@ -1,89 +0,0 @@
-package main
-
-import (
-	"context"
-	"log"
-
-	milvusclient "github.com/milvus-io/milvus/client/v2"
-	"github.com/milvus-io/milvus/client/v2/entity"
-)
-
-const (
-	milvusAddr     = `localhost:19530`
-	nEntities, dim = 3000, 128
-	collectionName = "hello_milvus"
-
-	msgFmt                         = "==== %s ====\n"
-	idCol, randomCol, embeddingCol = "ID", "random", "embeddings"
-	topK                           = 3
-)
-
-func main() {
-	ctx := context.Background()
-
-	log.Printf(msgFmt, "start connecting to Milvus")
-	c, err := milvusclient.New(ctx, &milvusclient.ClientConfig{
-		Address: milvusAddr,
-	})
-	if err != nil {
-		log.Fatal("failed to connect to milvus, err: ", err.Error())
-	}
-	defer c.Close(ctx)
-
-	dbNames, err := c.ListDatabase(ctx, milvusclient.NewListDatabaseOption())
-	if err != nil {
-		log.Fatal("failed to list databases", err.Error())
-	}
-	log.Println("=== Databases: ", dbNames)
-
-	schema := entity.NewSchema().WithName("hello_milvus").
-		WithField(entity.NewField().WithName("ID").WithDataType(entity.FieldTypeInt64).WithIsPrimaryKey(true)).
-		WithField(entity.NewField().WithName("Vector").WithDataType(entity.FieldTypeFloatVector).WithDim(128))
-
-	if err := c.CreateCollection(ctx, milvusclient.NewCreateCollectionOption("hello_milvus", schema)); err != nil {
-		log.Fatal("failed to create collection:", err.Error())
-	}
-
-	collections, err := c.ListCollections(ctx, milvusclient.NewListCollectionOption())
-	if err != nil {
-		log.Fatal("failed to list collections,", err.Error())
-	}
-
-	for _, collectionName := range collections {
-		collection, err := c.DescribeCollection(ctx, milvusclient.NewDescribeCollectionOption(collectionName))
-		if err != nil {
-			log.Fatal(err.Error())
-		}
-		log.Println(collection.Name)
-		for _, field := range collection.Schema.Fields {
-			log.Println("=== Field: ", field.Name, field.DataType, field.AutoID)
-		}
-	}
-
-	c.CreateDatabase(ctx, milvusclient.NewCreateDatabaseOption("test"))
-	c.UsingDatabase(ctx, milvusclient.NewUsingDatabaseOption("test"))
-
-	schema = entity.NewSchema().WithName("hello_milvus").
-		WithField(entity.NewField().WithName("ID").WithDataType(entity.FieldTypeVarChar).WithMaxLength(64).WithIsPrimaryKey(true)).
-		WithField(entity.NewField().WithName("Vector").WithDataType(entity.FieldTypeFloatVector).WithDim(128))
-
-	if err := c.CreateCollection(ctx, milvusclient.NewCreateCollectionOption("hello_milvus", schema)); err != nil {
-		log.Fatal("failed to create collection:", err.Error())
-	}
-
-	collections, err = c.ListCollections(ctx, milvusclient.NewListCollectionOption())
-	if err != nil {
-		log.Fatal("failed to list collections,", err.Error())
-	}
-
-	for _, collectionName := range collections {
-		collection, err := c.DescribeCollection(ctx, milvusclient.NewDescribeCollectionOption(collectionName))
-		if err != nil {
-			log.Fatal(err.Error())
-		}
-		log.Println(collection.Name)
-		for _, field := range collection.Schema.Fields {
-			log.Println("=== Field: ", field.Name, field.DataType, field.AutoID)
-		}
-	}
-}
diff --git a/client/example/playground/main.go b/client/example/playground/main.go
deleted file mode 100644
index 10b3256bcdfe5..0000000000000
--- a/client/example/playground/main.go
+++ /dev/null
@@ -1,326 +0,0 @@
-package main
-
-import (
-	"context"
-	"flag"
-	"log"
-	"math/rand"
-	"time"
-
-	milvusclient "github.com/milvus-io/milvus/client/v2"
-	"github.com/milvus-io/milvus/client/v2/entity"
-	"github.com/milvus-io/milvus/client/v2/index"
-)
-
-var cmd = flag.String("cmd", helloMilvusCmd, "command to run")
-
-const (
-	helloMilvusCmd = `hello_milvus`
-	partitionsCmd  = `partitions`
-	indexCmd       = `indexes`
-	countCmd       = `count`
-
-	milvusAddr     = `localhost:19530`
-	nEntities, dim = 3000, 128
-	collectionName = "hello_milvus"
-
-	msgFmt                         = "==== %s ====\n"
-	idCol, randomCol, embeddingCol = "ID", "random", "embeddings"
-	topK                           = 3
-)
-
-func main() {
-	flag.Parse()
-
-	switch *cmd {
-	case helloMilvusCmd:
-		HelloMilvus()
-	case partitionsCmd:
-		Partitions()
-	case indexCmd:
-		Indexes()
-	case countCmd:
-		Count()
-	}
-}
-
-func Count() {
-	ctx := context.Background()
-
-	collectionName := "hello_count_inverted"
-
-	c, err := milvusclient.New(ctx, &milvusclient.ClientConfig{
-		Address: "127.0.0.1:19530",
-	})
-	if err != nil {
-		log.Fatal("failed to connect to milvus, err: ", err.Error())
-	}
-
-	schema := entity.NewSchema().WithName(collectionName).
-		WithField(entity.NewField().WithName("id").WithDataType(entity.FieldTypeInt64).WithIsAutoID(true).WithIsPrimaryKey(true)).
-		WithField(entity.NewField().WithName("vector").WithDataType(entity.FieldTypeFloatVector).WithDim(128))
-
-	err = c.CreateCollection(ctx, milvusclient.NewCreateCollectionOption(collectionName, schema))
-	if err != nil {
-		log.Fatal("failed to connect to milvus, err: ", err.Error())
-	}
-
-	indexTask, err := c.CreateIndex(ctx, milvusclient.NewCreateIndexOption(collectionName, "id", index.NewGenericIndex("inverted", map[string]string{})))
-	if err != nil {
-		log.Fatal("failed to connect to milvus, err: ", err.Error())
-	}
-
-	indexTask.Await(ctx)
-
-	indexTask, err = c.CreateIndex(ctx, milvusclient.NewCreateIndexOption(collectionName, "vector", index.NewHNSWIndex(entity.L2, 16, 32)))
-	if err != nil {
-		log.Fatal("failed to connect to milvus, err: ", err.Error())
-	}
-
-	indexTask.Await(ctx)
-
-	loadTask, err := c.LoadCollection(ctx, milvusclient.NewLoadCollectionOption(collectionName))
-	if err != nil {
-		log.Fatal("faied to load collection, err: ", err.Error())
-	}
-	loadTask.Await(ctx)
-
-	for i := 0; i < 100; i++ {
-		// randomData := make([]int64, 0, nEntities)
-		vectorData := make([][]float32, 0, nEntities)
-		// generate data
-		for i := 0; i < nEntities; i++ {
-			// randomData = append(randomData, rand.Int63n(1000))
-			vec := make([]float32, 0, dim)
-			for j := 0; j < dim; j++ {
-				vec = append(vec, rand.Float32())
-			}
-			vectorData = append(vectorData, vec)
-		}
-
-		_, err = c.Insert(ctx, milvusclient.NewColumnBasedInsertOption(collectionName).WithFloatVectorColumn("vector", dim, vectorData))
-		if err != nil {
-			log.Fatal("failed to insert data")
-		}
-
-		log.Println("start flush collection")
-		flushTask, err := c.Flush(ctx, milvusclient.NewFlushOption(collectionName))
-		if err != nil {
-			log.Fatal("failed to flush", err.Error())
-		}
-		start := time.Now()
-		err = flushTask.Await(ctx)
-		if err != nil {
-			log.Fatal("failed to flush", err.Error())
-		}
-		log.Println("flush done, elapsed", time.Since(start))
-
-		result, err := c.Query(ctx, milvusclient.NewQueryOption(collectionName).
-			WithOutputFields("count(*)").
-			WithConsistencyLevel(entity.ClStrong))
-		if err != nil {
-			log.Fatal("failed to connect to milvus, err: ", err.Error())
-		}
-		for _, rs := range result.Fields {
-			log.Println(rs)
-		}
-		result, err = c.Query(ctx, milvusclient.NewQueryOption(collectionName).
-			WithOutputFields("count(*)").
-			WithFilter("id > 0").
-			WithConsistencyLevel(entity.ClStrong))
-		if err != nil {
-			log.Fatal("failed to connect to milvus, err: ", err.Error())
-		}
-		for _, rs := range result.Fields {
-			log.Println(rs)
-		}
-	}
-
-	err = c.DropCollection(ctx, milvusclient.NewDropCollectionOption(collectionName))
-	if err != nil {
-		log.Fatal("=== Failed to drop collection", err.Error())
-	}
-}
-
-func HelloMilvus() {
-	ctx := context.Background()
-
-	log.Printf(msgFmt, "start connecting to Milvus")
-	c, err := milvusclient.New(ctx, &milvusclient.ClientConfig{
-		Address: milvusAddr,
-	})
-	if err != nil {
-		log.Fatal("failed to connect to milvus, err: ", err.Error())
-	}
-	defer c.Close(ctx)
-
-	if has, err := c.HasCollection(ctx, milvusclient.NewHasCollectionOption(collectionName)); err != nil {
-		log.Fatal("failed to check collection exists or not", err.Error())
-	} else if has {
-		c.DropCollection(ctx, milvusclient.NewDropCollectionOption(collectionName))
-	}
-
-	err = c.CreateCollection(ctx, milvusclient.SimpleCreateCollectionOptions(collectionName, dim).WithVarcharPK(true, 128))
-	if err != nil {
-		log.Fatal("failed to create collection", err.Error())
-	}
-
-	collections, err := c.ListCollections(ctx, milvusclient.NewListCollectionOption())
-	if err != nil {
-		log.Fatal("failed to list collections,", err.Error())
-	}
-
-	for _, collectionName := range collections {
-		collection, err := c.DescribeCollection(ctx, milvusclient.NewDescribeCollectionOption(collectionName))
-		if err != nil {
-			log.Fatal(err.Error())
-		}
-		log.Println(collection.Name)
-		for _, field := range collection.Schema.Fields {
-			log.Println("=== Field: ", field.Name, field.DataType, field.AutoID)
-		}
-	}
-
-	// randomData := make([]int64, 0, nEntities)
-	vectorData := make([][]float32, 0, nEntities)
-	// generate data
-	for i := 0; i < nEntities; i++ {
-		// randomData = append(randomData, rand.Int63n(1000))
-		vec := make([]float32, 0, dim)
-		for j := 0; j < dim; j++ {
-			vec = append(vec, rand.Float32())
-		}
-		vectorData = append(vectorData, vec)
-	}
-
-	_, err = c.Insert(ctx, milvusclient.NewColumnBasedInsertOption(collectionName).WithFloatVectorColumn("vector", dim, vectorData))
-	if err != nil {
-		log.Fatal("failed to insert data")
-	}
-
-	log.Println("start flush collection")
-	flushTask, err := c.Flush(ctx, milvusclient.NewFlushOption(collectionName))
-	if err != nil {
-		log.Fatal("failed to flush", err.Error())
-	}
-	start := time.Now()
-	err = flushTask.Await(ctx)
-	if err != nil {
-		log.Fatal("failed to flush", err.Error())
-	}
-	log.Println("flush done, elapsed", time.Since(start))
-
-	vec2search := []entity.Vector{
-		entity.FloatVector(vectorData[len(vectorData)-2]),
-		entity.FloatVector(vectorData[len(vectorData)-1]),
-	}
-
-	resultSets, err := c.Search(ctx, milvusclient.NewSearchOption(collectionName, 3, vec2search).WithConsistencyLevel(entity.ClEventually))
-	if err != nil {
-		log.Fatal("failed to search collection", err.Error())
-	}
-	for _, resultSet := range resultSets {
-		for i := 0; i < resultSet.ResultCount; i++ {
-			log.Print(resultSet.IDs.Get(i))
-		}
-		log.Println()
-	}
-
-	err = c.DropCollection(ctx, milvusclient.NewDropCollectionOption(collectionName))
-	if err != nil {
-		log.Fatal("=== Failed to drop collection", err.Error())
-	}
-}
-
-func Partitions() {
-	ctx := context.Background()
-
-	log.Printf(msgFmt, "start connecting to Milvus")
-	c, err := milvusclient.New(ctx, &milvusclient.ClientConfig{
-		Address: milvusAddr,
-	})
-	if err != nil {
-		log.Fatal("failed to connect to milvus, err: ", err.Error())
-	}
-	defer c.Close(ctx)
-
-	has, err := c.HasCollection(ctx, milvusclient.NewHasCollectionOption(collectionName))
-	if err != nil {
-		log.Fatal(err)
-	}
-	if has {
-		c.DropCollection(ctx, milvusclient.NewDropCollectionOption(collectionName))
-	}
-
-	err = c.CreateCollection(ctx, milvusclient.SimpleCreateCollectionOptions(collectionName, dim))
-	if err != nil {
-		log.Fatal("failed to create collection", err.Error())
-	}
-
-	partitions, err := c.ListPartitions(ctx, milvusclient.NewListPartitionOption(collectionName))
-	if err != nil {
-		log.Fatal("failed to create collection", err.Error())
-	}
-
-	for _, partitionName := range partitions {
-		err := c.DropPartition(ctx, milvusclient.NewDropPartitionOption(collectionName, partitionName))
-		if err != nil {
-			log.Println(err.Error())
-		}
-	}
-
-	c.CreatePartition(ctx, milvusclient.NewCreatePartitionOption(collectionName, "new_partition"))
-	partitions, err = c.ListPartitions(ctx, milvusclient.NewListPartitionOption(collectionName))
-	if err != nil {
-		log.Fatal("failed to create collection", err.Error())
-	}
-	log.Println(partitions)
-
-	err = c.DropCollection(ctx, milvusclient.NewDropCollectionOption(collectionName))
-	if err != nil {
-		log.Fatal("=== Failed to drop collection", err.Error())
-	}
-}
-
-func Indexes() {
-	ctx := context.Background()
-
-	log.Printf(msgFmt, "start connecting to Milvus")
-	c, err := milvusclient.New(ctx, &milvusclient.ClientConfig{
-		Address: milvusAddr,
-	})
-	if err != nil {
-		log.Fatal("failed to connect to milvus, err: ", err.Error())
-	}
-	defer c.Close(ctx)
-
-	has, err := c.HasCollection(ctx, milvusclient.NewHasCollectionOption(collectionName))
-	if err != nil {
-		log.Fatal(err)
-	}
-	if has {
-		c.DropCollection(ctx, milvusclient.NewDropCollectionOption(collectionName))
-	}
-
-	err = c.CreateCollection(ctx, milvusclient.SimpleCreateCollectionOptions(collectionName, dim))
-	if err != nil {
-		log.Fatal("failed to create collection", err.Error())
-	}
-
-	index := index.NewHNSWIndex(entity.COSINE, 16, 64)
-
-	createIdxOpt := milvusclient.NewCreateIndexOption(collectionName, "vector", index)
-	task, err := c.CreateIndex(ctx, createIdxOpt)
-	if err != nil {
-		log.Fatal("failed to create index", err.Error())
-	}
-	task.Await(ctx)
-
-	indexes, err := c.ListIndexes(ctx, milvusclient.NewListIndexOption(collectionName))
-	if err != nil {
-		log.Fatal("failed to list indexes", err.Error())
-	}
-	for _, indexName := range indexes {
-		log.Println(indexName)
-	}
-}
diff --git a/client/example/rowbase/main.go b/client/example/rowbase/main.go
deleted file mode 100644
index 2b43378bb8071..0000000000000
--- a/client/example/rowbase/main.go
+++ /dev/null
@@ -1,87 +0,0 @@
-package main
-
-import (
-	"context"
-	"log"
-	"math/rand"
-
-	"github.com/samber/lo"
-
-	milvusclient "github.com/milvus-io/milvus/client/v2"
-	"github.com/milvus-io/milvus/client/v2/row"
-)
-
-type Data struct {
-	ID     int64     `milvus:"name:id;primary_key;auto_id"`
-	Vector []float32 `milvus:"name:vector;dim:128"`
-}
-
-const (
-	milvusAddr     = `localhost:19530`
-	nEntities, dim = 10, 128
-	collectionName = "hello_row_base"
-
-	msgFmt                         = "==== %s ====\n"
-	idCol, randomCol, embeddingCol = "id", "random", "vector"
-	topK                           = 3
-)
-
-func main() {
-	schema, err := row.ParseSchema(&Data{})
-	if err != nil {
-		log.Fatal("failed to parse schema from struct", err.Error())
-	}
-
-	for _, field := range schema.Fields {
-		log.Printf("Field name: %s, FieldType %s, IsPrimaryKey: %t", field.Name, field.DataType, field.PrimaryKey)
-	}
-	schema.WithName(collectionName)
-
-	ctx := context.Background()
-
-	log.Printf(msgFmt, "start connecting to Milvus")
-	c, err := milvusclient.New(ctx, &milvusclient.ClientConfig{
-		Address: milvusAddr,
-	})
-	if err != nil {
-		log.Fatal("failed to connect to milvus, err: ", err.Error())
-	}
-	defer c.Close(ctx)
-
-	if has, err := c.HasCollection(ctx, milvusclient.NewHasCollectionOption(collectionName)); err != nil {
-		log.Fatal("failed to check collection exists or not", err.Error())
-	} else if has {
-		log.Printf("collection %s alread exists, dropping it now\n", collectionName)
-		c.DropCollection(ctx, milvusclient.NewDropCollectionOption(collectionName))
-	}
-
-	err = c.CreateCollection(ctx, milvusclient.NewCreateCollectionOption(collectionName, schema))
-	if err != nil {
-		log.Fatal("failed to create collection", err.Error())
-	}
-
-	var rows []*Data
-	for i := 0; i < nEntities; i++ {
-		vec := make([]float32, 0, dim)
-		for j := 0; j < dim; j++ {
-			vec = append(vec, rand.Float32())
-		}
-		rows = append(rows, &Data{
-			Vector: vec,
-		})
-	}
-
-	insertResult, err := c.Insert(ctx, milvusclient.NewRowBasedInsertOption(collectionName, lo.Map(rows, func(data *Data, _ int) any {
-		return data
-	})...))
-	if err != nil {
-		log.Fatal("failed to insert data: ", err.Error())
-	}
-	log.Println(insertResult.IDs)
-	for _, row := range rows {
-		// id shall be written back
-		log.Println(row.ID)
-	}
-
-	c.DropCollection(ctx, milvusclient.NewDropCollectionOption(collectionName))
-}
diff --git a/scripts/run_go_codecov.sh b/scripts/run_go_codecov.sh
index 1e8ca87e5f928..57231534341f3 100755
--- a/scripts/run_go_codecov.sh
+++ b/scripts/run_go_codecov.sh
@@ -73,5 +73,5 @@ endTime=`date +%s`
 echo "Total time for go unittest:" $(($endTime-$beginTime)) "s"
 
 # generate html report
-go tool cover -html=./${FILE_COVERAGE_INFO} -o ./${FILE_COVERAGE_HTML}
-echo "Generate go coverage report to ${FILE_COVERAGE_HTML}"
+# go tool cover -html=./${FILE_COVERAGE_INFO} -o ./${FILE_COVERAGE_HTML}
+# echo "Generate go coverage report to ${FILE_COVERAGE_HTML}"