type (
		Level0 struct {
			ID       uint
			Value    string
			Level1ID uint
		}
		Level1 struct {
			ID         uint
			Value      string
			Level2ID   *uint
			Level2_1ID *uint
			Level0s    []Level0 `json:",omitempty"`
		}
		Level2 struct {
			ID       uint
			Level1s  []Level1
			Level3ID uint
		}
		Level2_1 struct {
			ID       uint
			Level1s  []Level1 `json:",omitempty"`

	}
}

func TestForeignKeyConstraints(t *testing.T) {
	tidbSkip(t, "not support the foreign key feature")

	type Profile struct {
		ID       uint
		Name     string
		MemberID uint
	}

	type Member struct {
		ID      uint
		Refer   uint `gorm:"uniqueIndex"`
		Name    string
		Profile Profile `gorm:"Constraint:OnUpdate:CASCADE,OnDelete:CASCADE;FOREIGNKEY:MemberID;References:Refer"`
	}

// buffer becomes too large, ReadFrom will panic with [ErrTooLarge].
func (b *Buffer) ReadFrom(r io.Reader) (n int64, err error) {
	b.lastRead = opInvalid
	for {
		i := b.grow(MinRead)
		b.buf = b.buf[:i]
		m, e := r.Read(b.buf[i:cap(b.buf)])
		if m < 0 {
			panic(errNegativeRead)
		}

		b.buf = b.buf[:i+m]
		n += int64(m)
		if e == io.EOF {
			return n, nil // e is EOF, so return nil explicitly
		}
		if e != nil {

				Index:      []uint8(nil),
				Checksums:  map[string]string(nil),
			},
		},
		Erasure: ErasureInfo{
			Algorithm:    "ReedSolomon",
			DataBlocks:   6,
			ParityBlocks: 6,
			BlockSize:    1048576,
			Index:        1,
			Distribution: []int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12},
			Checksums:    []ChecksumInfo{{PartNumber: 1, Algorithm: 0x3, Hash: []uint8{}}},
		},
		NumVersions: 1,

	type (
		Preload struct {
			ID       uint
			Value    string
			NestedID uint
		}
		Join struct {
			ID       uint
			Value    string
			NestedID uint
		}
		Nested struct {
			ID       uint
			Preloads []*Preload
			Join     Join
			ValueID  uint
		}
		Value struct {
			ID     uint
			Name   string
			Nested Nested
		}
	)

	CopyObjectPart(ctx context.Context, srcBucket, srcObject, destBucket, destObject string, uploadID string, partID int,
		startOffset int64, length int64, srcInfo ObjectInfo, srcOpts, dstOpts ObjectOptions) (info PartInfo, err error)
	PutObjectPart(ctx context.Context, bucket, object, uploadID string, partID int, data *PutObjReader, opts ObjectOptions) (info PartInfo, err error)

	type (
		Furniture struct {
			gorm.Model
			OwnerID *uint
		}

		Owner struct {
			gorm.Model
			Furnitures []Furniture
			CompanyID  *uint
			Company    Company
		}

		Building struct {
			gorm.Model
			Name    string
			OwnerID *uint
			Owner   Owner
		}
	)

	DB.Migrator().DropTable(&Building{}, &Owner{}, &Furniture{})

		{Name: "company_count_group_c"},
	})

	var count1 int64
	if err := DB.Model(&Company{}).Where("name = ?", "company_count_group_a").Group("name").Count(&count1).Error; err != nil {
		t.Errorf(fmt.Sprintf("Count should work, but got err %v", err))
	}
	if count1 != 1 {
		t.Errorf("Count with group should be 1, but got count: %v", count1)
	}

	var count2 int64

		12: {bucketName: bucket, objName: object, inputData: []byte("ijkl"), inputMeta: map[string]string{"etag": "09a0877d04abf8759f99adec02baf579"}, inputDataSize: int64(len("ijkl"))},
		13: {bucketName: bucket, objName: object, inputData: []byte("mnop"), inputMeta: map[string]string{"etag": "e132e96a5ddad6da8b07bba6f6131fef"}, inputDataSize: int64(len("mnop"))},

		// With no metadata

	bts := make([]byte, 0, v.Msgsize())
	bts, _ = v.MarshalMsg(bts[0:0])
	b.SetBytes(int64(len(bts)))
	b.ReportAllocs()
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		bts, _ = v.MarshalMsg(bts[0:0])
	}
}

func BenchmarkUnmarshalRStat(b *testing.B) {
	v := RStat{}
	bts, _ := v.MarshalMsg(nil)
	b.ReportAllocs()
	b.SetBytes(int64(len(bts)))
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		_, err := v.UnmarshalMsg(bts)