Skip to Navigation
Session: Deleting Entities
Entities can be marked for deletion by using the Delete method, but will not be removed from the server until SaveChanges is called.
Syntax
void Delete<T>(T entity);
void Delete(string id);
void Delete(string id, string expectedChangeVector);| Parameters | ||
|---|---|---|
| entity or id | T or string | instance of the entity to delete or entity ID |
| expectedChangeVector | string | a change vector to use for concurrency checks |
Example I
Employee employee = session.Load<Employee>("employees/1");
session.Delete(employee);
session.SaveChanges();Employee employee = await session.LoadAsync<Employee>("employees/1");
session.Delete(employee);
await session.SaveChangesAsync();Concurrency on Delete
If UseOptimisticConcurrency is set to 'true' (default 'false'), the Delete() method will use loaded 'employees/1' change vector for concurrency check and might throw ConcurrencyException.
Example II
session.Delete("employees/1");
session.SaveChanges();session.Delete("employees/1");
await session.SaveChangesAsync();Concurrency on Delete
In this overload, the Delete() method will not do any change vector based concurrency checks because the change vector for 'employees/1' is unknown.
Information
If entity is not tracked by session, then executing
session.Delete("employees/1");is equal to doing
session.Advanced.Defer(new DeleteCommandData("employees/1", changeVector: null));Change Vector in DeleteCommandData
In this sample the change vector is null - this means that there will be no concurrency checks. A non-null and valid change vector value will trigger a concurrency check.
You can read more about defer operations here.
Related Articles