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Session : Deleting entities

Entities can be marked for deletion by using Delete method, but will not be removed from server until SaveChanges is called.

Syntax

void Delete<T>(T entity);

void Delete<T>(ValueType id);

void Delete(string id);

Parameters
entity or id T, ValueType or string instance of entity to delete or entity Id

Example 1

// if UseOptimisticConcurrency is set to 'true' (default 'false')
// this 'Delete' method will use loaded 'employees/1' etag for concurrency check
// and might throw ConcurrencyException
Employee employee = session.Load<Employee>("employees/1");
session.Delete(employee);
session.SaveChanges();

Example 2

// this 'Delete' method will not do any Etag-based concurrency checks
// because Etag for 'employees/1' is unknown
session.Delete("employees/1");
session.SaveChanges();

Information

If entity is not tracked by session, then executing

session.Delete("employees/1");

is equal to doing

session.Advanced.Defer(new DeleteCommandData { Key = "employees/1" });

You can read more about defer operations here.