historyFile := pathJoin(minioConfigHistoryPrefix, uuidKV+kvPrefix)
	_, err := objAPI.DeleteObject(ctx, minioMetaBucket, historyFile, ObjectOptions{
		DeletePrefix:       true,
		DeletePrefixObject: true, // use prefix delete on exact object (this is an optimization to avoid fan-out calls)
	})
	return err
}

func readServerConfigHistory(ctx context.Context, objAPI ObjectLayer, uuidKV string) ([]byte, error) {

}

func (cs *callbacks) Query() *processor {
	return cs.processors["query"]
}

func (cs *callbacks) Update() *processor {
	return cs.processors["update"]
}

func (cs *callbacks) Delete() *processor {
	return cs.processors["delete"]
}

func (cs *callbacks) Row() *processor {
	return cs.processors["row"]
}

func (cs *callbacks) Raw() *processor {
	return cs.processors["raw"]
}

	}
	if reply = locksHeld == WriteLock; !reply { // Unless it is a write lock
		return false, fmt.Errorf("Unlock attempted on a read locked entity: %s (%d read locks active)", args.Resources[0], locksHeld)
	}
	delete(l.lockMap, args.Resources[0]) // Remove the write lock
	return true, nil
}

const ReadLock = 1

func (l *lockServer) RLock(args *LockArgs) (reply bool, err error) {

			return nil
		}
		return err
	}
	if inuse, err := d.InUse(ctx); err != nil {
		return err
	} else if inuse {
		return errTierBackendNotEmpty
	}
	config.Lock()
	delete(config.Tiers, tier)
	delete(config.drivercache, tier)
	config.Unlock()
	return nil
}

// Verify verifies if tier's config is valid by performing all supported
// operations on the corresponding warmbackend.

	if count1 <= 0 {
		t.Errorf("Should find some users")
	}

	if DB.Where("name = ?", "jinzhu; delete * from users").First(&User{}).Error == nil {
		t.Errorf("Should got error with invalid SQL")
	}

	DB.Model(&User{}).Count(&count2)
	if count1 != count2 {
		t.Errorf("No user should not be deleted by invalid SQL")
	}
}

func TestSetAndGet(t *testing.T) {

	VersionID string `xml:"VersionId"`
}

// DeleteObjectsResponse container for multiple object deletes.
type DeleteObjectsResponse struct {
	XMLName xml.Name `xml:"http://s3.amazonaws.com/doc/2006-03-01/ DeleteResult" json:"-"`

	// Collection of all deleted objects
	DeletedObjects []DeletedObject `xml:"Deleted,omitempty"`

	// Collection of errors deleting certain objects.
	Errors []DeleteError `xml:"Error,omitempty"`

	// Objects total count across all buckets
	ObjectsTotalCount uint64 `json:"objectsCount"`

	// Versions total count across all buckets
	VersionsTotalCount uint64 `json:"versionsCount"`

	// Delete markers total count across all buckets
	DeleteMarkersTotalCount uint64 `json:"deleteMarkersCount"`

	// Objects total size across all buckets
	ObjectsTotalSize uint64                           `json:"objectsTotalSize"`

	ETag string

	// Version ID of this object.
	VersionID string

	// IsLatest indicates if this is the latest current version
	// latest can be true for delete marker or a version.
	IsLatest bool

	// DeleteMarker indicates if the versionId corresponds
	// to a delete marker on an object.
	DeleteMarker bool

	// Transitioned object information
	TransitionedObject TransitionedObject

	QueryClauses(*Field) []clause.Interface
}

// UpdateClausesInterface update clauses interface
type UpdateClausesInterface interface {
	UpdateClauses(*Field) []clause.Interface
}

// DeleteClausesInterface delete clauses interface
type DeleteClausesInterface interface {
	DeleteClauses(*Field) []clause.Interface

	var err error
	if _, err = objAPI.GetBucketInfo(ctx, bucket, BucketOptions{}); err != nil {
		writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
		return
	}

	// Delete bucket encryption config from object layer
	updatedAt, err := globalBucketMetadataSys.Delete(ctx, bucket, bucketSSEConfig)
	if err != nil {
		writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
		return
	}

	// Call site replication hook.