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OleDbConnection.BeginTransaction Method

Definition

Starts a database transaction.

Overloads

BeginTransaction()

Starts a database transaction with the current IsolationLevel value.

BeginTransaction(IsolationLevel)

Starts a database transaction with the specified isolation level.

BeginTransaction()

Source:
OleDbConnection.cs
Source:
OleDbConnection.cs

Starts a database transaction with the current IsolationLevel value.

public:
 System::Data::OleDb::OleDbTransaction ^ BeginTransaction();
public System.Data.OleDb.OleDbTransaction BeginTransaction ();
override this.BeginTransaction : unit -> System.Data.OleDb.OleDbTransaction
member this.BeginTransaction : unit -> System.Data.OleDb.OleDbTransaction
Public Function BeginTransaction () As OleDbTransaction

Returns

An object representing the new transaction.

Exceptions

Parallel transactions are not supported.

Examples

The following example creates an OleDbConnection and an OleDbTransaction. It also demonstrates how to use the BeginTransaction, Commit, and Rollback methods.

public void ExecuteTransaction(string connectionString)
{
    using (OleDbConnection connection =
               new OleDbConnection(connectionString))
    {
        OleDbCommand command = new OleDbCommand();
        OleDbTransaction transaction = null;

        // Set the Connection to the new OleDbConnection.
        command.Connection = connection;

        // Open the connection and execute the transaction.
        try
        {
            connection.Open();

            // Start a local transaction with ReadCommitted isolation level.
            transaction = connection.BeginTransaction(IsolationLevel.ReadCommitted);

            // Assign transaction object for a pending local transaction.
            command.Connection = connection;
            command.Transaction = transaction;

            // Execute the commands.
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')";
            command.ExecuteNonQuery();
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')";
            command.ExecuteNonQuery();

            // Commit the transaction.
            transaction.Commit();
            Console.WriteLine("Both records are written to database.");
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
            try
            {
                // Attempt to roll back the transaction.
                transaction.Rollback();
            }
            catch
            {
                // Do nothing here; transaction is not active.
            }
        }
        // The connection is automatically closed when the
        // code exits the using block.
    }
}
Public Sub ExecuteTransaction(ByVal connectionString As String)

    Using connection As New OleDbConnection(connectionString)
        Dim command As New OleDbCommand()
        Dim transaction As OleDbTransaction

        ' Set the Connection to the new OleDbConnection.
        command.Connection = connection

        ' Open the connection and execute the transaction.
        Try
            connection.Open()

            ' Start a local transaction with ReadCommitted isolation level.
            transaction = connection.BeginTransaction(IsolationLevel.ReadCommitted)

            ' Assign transaction object for a pending local transaction.
            command.Connection = connection
            command.Transaction = transaction

            ' Execute the commands.
            command.CommandText = _
                "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')"
            command.ExecuteNonQuery()
            command.CommandText = _
                "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')"
            command.ExecuteNonQuery()

            ' Commit the transaction.
            transaction.Commit()
            Console.WriteLine("Both records are written to database.")

        Catch ex As Exception
            Console.WriteLine(ex.Message)
            ' Try to rollback the transaction
            Try
                    transaction.Rollback()

            Catch
                ' Do nothing here; transaction is not active.
            End Try
        End Try
        ' The connection is automatically closed when the
        ' code exits the Using block.
    End Using
End Sub

Remarks

You must explicitly commit or roll back the transaction using the Commit or Rollback method. To make sure that the .NET Framework Data Provider for OLE DB transaction management model performs correctly, avoid using other transaction management models, such as those provided by the data source.

See also

Applies to

BeginTransaction(IsolationLevel)

Source:
OleDbConnection.cs
Source:
OleDbConnection.cs

Starts a database transaction with the specified isolation level.

public:
 System::Data::OleDb::OleDbTransaction ^ BeginTransaction(System::Data::IsolationLevel isolationLevel);
public System.Data.OleDb.OleDbTransaction BeginTransaction (System.Data.IsolationLevel isolationLevel);
override this.BeginTransaction : System.Data.IsolationLevel -> System.Data.OleDb.OleDbTransaction
member this.BeginTransaction : System.Data.IsolationLevel -> System.Data.OleDb.OleDbTransaction
Public Function BeginTransaction (isolationLevel As IsolationLevel) As OleDbTransaction

Parameters

isolationLevel
IsolationLevel

The isolation level under which the transaction should run.

Returns

An object representing the new transaction.

Exceptions

Parallel transactions are not supported.

Examples

The following example creates an OleDbConnection and an OleDbTransaction. It also demonstrates how to use the BeginTransaction, a Commit, and Rollback methods.

public void ExecuteTransaction(string connectionString)
{
    using (OleDbConnection connection =
               new OleDbConnection(connectionString))
    {
        OleDbCommand command = new OleDbCommand();
        OleDbTransaction transaction = null;

        // Set the Connection to the new OleDbConnection.
        command.Connection = connection;

        // Open the connection and execute the transaction.
        try
        {
            connection.Open();

            // Start a local transaction
            transaction = connection.BeginTransaction();

            // Assign transaction object for a pending local transaction.
            command.Connection = connection;
            command.Transaction = transaction;

            // Execute the commands.
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')";
            command.ExecuteNonQuery();
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')";
            command.ExecuteNonQuery();

            // Commit the transaction.
            transaction.Commit();
            Console.WriteLine("Both records are written to database.");
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
            try
            {
                // Attempt to roll back the transaction.
                transaction.Rollback();
            }
            catch
            {
                // Do nothing here; transaction is not active.
            }
        }
        // The connection is automatically closed when the
        // code exits the using block.
    }
}
Public Sub ExecuteTransaction(ByVal connectionString As String)

    Using connection As New OleDbConnection(connectionString)
        Dim command As New OleDbCommand()
        Dim transaction As OleDbTransaction

        ' Set the Connection to the new OleDbConnection.
        command.Connection = connection

        ' Open the connection and execute the transaction.
        Try
            connection.Open()

            ' Start a local transaction.
            transaction = connection.BeginTransaction()

            ' Assign transaction object for a pending local transaction.
            command.Connection = connection
            command.Transaction = transaction

            ' Execute the commands.
            command.CommandText = _
                "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')"
            command.ExecuteNonQuery()
            command.CommandText = _
                "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')"
            command.ExecuteNonQuery()

            ' Commit the transaction.
            transaction.Commit()
            Console.WriteLine("Both records are written to database.")

        Catch ex As Exception
            Console.WriteLine(ex.Message)
            ' Try to rollback the transaction
            Try
                    transaction.Rollback()

            Catch
                ' Do nothing here; transaction is not active.
            End Try
        End Try
        ' The connection is automatically closed when the
        ' code exits the Using block.
    End Using
End Sub

Remarks

You must explicitly commit or roll back the transaction using the Commit or Rollback method. To make sure that the .NET Framework Data Provider for OLE DB transaction management model performs correctly, avoid using other transaction management models, such as those provided by the data source.

Note

If you do not specify an isolation level, the default isolation level for the underlying provider is used. To specify an isolation level with the BeginTransaction method, use the overload that takes the isolationLevel parameter.

See also

Applies to