MergeOption MergeOption MergeOption MergeOption Enum


Determines the synchronization option for sending or receiving entities to or from WCF Data Services.

public enum class MergeOption
public enum MergeOption
type MergeOption = 
Public Enum MergeOption


AppendOnly AppendOnly AppendOnly AppendOnly 0

Append new entities only. Existing entities or their original values will not be modified. No client-side changes are lost in this merge. This is the default behavior.

NoTracking NoTracking NoTracking NoTracking 3

Objects are always loaded from persisted storage. Any property changes made to objects in the object context are overwritten by the data source values.

OverwriteChanges OverwriteChanges OverwriteChanges OverwriteChanges 1

All current values on the client are overwritten with current values from the data service regardless of whether they have been changed on the client.

PreserveChanges PreserveChanges PreserveChanges PreserveChanges 2

Current values that have been changed on the client are not modified, but any unchanged values are updated with current values from the data service. No client-side changes are lost in this merge.


This value is used when materializing objects. Set this property to the appropriate materialization option before executing any queries or updates to the data service. The default value is MergeOption.AppendOnly.

Applies to

See also