AppContinuity.cs

usingSystem;
usingSystem.Threading;
usingSystem.Transactions;
//using Oracle.DataAccess.Client;
usingOracle.ManagedDataAccess.Client;

namespaceAppContinuity
{
classProgram
{
staticvoidMain(string[]args)
{

//Demo: ODP.NET Application Continuity
//Demonstrates that applications can recover and continue after 
// recoverable errors without end user disruption. Recoverable errors
// are errors that arise due to an external system failure, 
// independent of the application session logic that is executing. 
// Recoverable errors occur following planned and unplanned outages 
// of foregrounds, networks, nodes, storage, and databases, such as a 
// network outage, instance failure, hardware failure, network failure, 
// configuration change, or patching.

//To use Application Continuity with ODP.NET, set 
// Application Continuity=true (default) in the connection string.

//Setup instructions:
// A) On the database server :
// 1) Setup HR schema by using script %ORACLE_HOME%\demo\schema\human_resources\hr_main.sql 
// if not already available.
// 2) Run "GRANT execute on DBMS_APP_CONT to HR;" so that ODP.NET can determine the 
// in-flight transaction status following a recoverable error.
// B) In client app, modify the following connection attributes in this sample code:
// 1) Password: Password you specified while setting up HR schema setup.
// 2) Data Source: Connection descriptor or TNS alias to connect to the database.
// 3) Use the Oracle.ManagedDataAccess.Client namespace for managed ODP.NET or ODP.NET Core. 
// Or use Oracle.Data.Client namespace for unmanaged ODP.NET.
// Be sure to use a minimum version of ODP.NET Core 23c, managed ODP.NET 23c, or unmanaged ODP.NET 12.2 for AC support.

//Runtime instructions:
// You can intermittently execute the following command on the database
// to simulate a recoverable error condition and observe AC in action:
// "Execute dbms_service.disconnect_session('your service', dbms_service.immediate );"
//
// With Application Continuity enabled, the end user will observe 
// no error message, only a slight delayed execution.

//Provide user id and password for Oracle user 
stringconString="User Id=hr;Password=<password>;"+

//Provide Oracle data source info.
"Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=<hostname or IP>)(PORT=<port>))(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=<service name>)));";

//Loop infinitely
while(true)
{
try
{
using(OracleConnectioncon=newOracleConnection(conString))
{
using(OracleCommandcmd=con.CreateCommand())
{
//Start transaction
using(TransactionScopescope=newTransactionScope())
{
con.Open();
cmd.CommandText="update employees set salary=salary+1 where employee_id = 100";

cmd.ExecuteNonQuery();

//Commit
scope.Complete();

Console.WriteLine("Salary incremented.");
}
//Sleep for 1 second
Thread.Sleep(1000);
}
}
}
catch(Exceptionex)
{
Console.WriteLine(ex.Message);
}
}
}
}
}

/* Copyright (c) 2019, 2023 Oracle and/or its affiliates. All rights reserved. */

/******************************************************************************
 *
 * You may not use the identified files except in compliance with The MIT
 * License (the "License.")
 *
 * You may obtain a copy of the License at
 * https://github.com/oracle/Oracle.NET/blob/master/LICENSE
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 *****************************************************************************/