ADO.NET предоставляет очень полезный класс под названием SqlDependency.Вы можете подписаться на событие OnChange при изменении указанной таблицы в базе данных.
Вот документация и пример:
http://msdn.microsoft.com/en-us/library/62xk7953.aspx
Это выглядит очень хорошо и работает!
void Initialization()
{
// Create a dependency connection.
SqlDependency.Start(connectionString, queueName);
}
void SomeMethod()
{
// Assume connection is an open SqlConnection.
// Create a new SqlCommand object.
using (SqlCommand command=new SqlCommand(
"SELECT ShipperID, CompanyName, Phone FROM dbo.Shippers",
connection))
{
// Create a dependency and associate it with the SqlCommand.
SqlDependency dependency=new SqlDependency(command);
// Maintain the refence in a class member.
// Subscribe to the SqlDependency event.
dependency.OnChange+=new
OnChangeEventHandler(OnDependencyChange);
// Execute the command.
using (SqlDataReader reader = command.ExecuteReader())
{
// Process the DataReader.
}
}
}
// Handler method
void OnDependencyChange(object sender,
SqlNotificationEventArgs e )
{
// Handle the event (for example, invalidate this cache entry).
}
void Termination()
{
// Release the dependency.
SqlDependency.Stop(connectionString, queueName);
}
Однако для получения этих уведомлений вам необходимо включить компонент Service Broker в вашей базе данных.Вот как это сделать:
--Create login if you do not have already
--Example:
--CREATE LOGIN ChangesMonitor WITH PASSWORD = 'ChangesMonitor' ;
--GO
--Create user associated with this login and
--add provilages in Management Studio tab Security->Users
--(not sure if all are needed, but for test purposes add following):
--db_datareader, db_datawriter, db_ddladmin, db_accesadmin, db_owner, db_securityadmin
--must have exclusiveness on database
--script for database SqlDependExample and for user ChangesMonitor
ALTER DATABASE SqlDependExample SET ENABLE_BROKER
GO
GRANT CREATE PROCEDURE TO [ChangesMonitor];
GO
GRANT CREATE SERVICE TO [ChangesMonitor];
GO
GRANT CREATE QUEUE TO [ChangesMonitor];
GO
GRANT REFERENCES ON CONTRACT::[http://schemas.microsoft.com/SQL/Notifications/PostQueryNotification] TO [ChangesMonitor];
GO
GRANT SUBSCRIBE QUERY NOTIFICATIONS TO [ChangesMonitor];
GO
GRANT CONTROL ON SCHEMA::[dbo] TO [ChangesMonitor];
GO
GRANT IMPERSONATE ON USER::DBO TO [ChangesMonitor];
GO