Submit changes of only one entity

Question

If I select many rows from one table with one instance of DataContext. And then do I some changes in properties in the rows, can I submit changes to database only for one of the selected rows?

Answer 1

Yes you can.

First you need to isolate the entities you want to undo the changes. Then, you can use your DataContext class to Override those entities with the values from the Database.

MyEntity e1, e2, e3 // changed entities
...
// keep the changes only for e3
List<MyEntity> undoList = new List<MyEntity>();
undoList.Add(e1);
undoList.Add(e2);
myDataContext.Refresh(RefreshMode.OverwriteCurrentValues, undoList);

myDataContext.SubmitChanges();

EDIT:

You can track all the changed objects in the DataContext like this:

MyEntity changedEntityToSubmit; // first you need to know what is the entity you need to submit.
List<object> allChangedEntities = new List<object>(myDataContext.GetChangeSet().Updates);
allChangedEntities.Remove(changedEntityToSubmit);

myDataContext.Refresh(RefreshMode.OverwriteCurrentValues, allChangedEntities);

myDataContext.SubmitChanges();

This code is only considering the Updates. You also might need to consider the changes in Inserts and Deletes. This is up to you.