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OdbcConnection.BeginTransaction Method

Definition

Starts a transaction at the data source.

Overloads

BeginTransaction()

Starts a transaction at the data source.

BeginTransaction(IsolationLevel)

Starts a transaction at the data source with the specified IsolationLevel value.

BeginTransaction()

Source:
OdbcConnection.cs
Source:
OdbcConnection.cs

Starts a transaction at the data source.

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

Returns

An object representing the new transaction.

Exceptions

A transaction is currently active. Parallel transactions are not supported.

Examples

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

public static void ExecuteTransaction(string connectionString)
{
    using (OdbcConnection connection =
               new OdbcConnection(connectionString))
    {
        OdbcCommand command = new OdbcCommand();
        OdbcTransaction transaction = null;

        // Set the Connection to the new OdbcConnection.
        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 OdbcConnection(connectionString)
        Dim command As New OdbcCommand()
        Dim transaction As OdbcTransaction

        ' Set the Connection to the new OdbcConnection.
        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

To commit or roll back the transaction, you must explicitly use the Commit or Rollback methods.

To make sure that the .NET Framework Data Provider for ODBC 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 isolation level will be determined by the driver being used. To specify an isolation level with the BeginTransaction method, use the overload that takes the isolevel parameter.

See also

Applies to

BeginTransaction(IsolationLevel)

Source:
OdbcConnection.cs
Source:
OdbcConnection.cs

Starts a transaction at the data source with the specified IsolationLevel value.

public:
 System::Data::Odbc::OdbcTransaction ^ BeginTransaction(System::Data::IsolationLevel isolevel);
public System.Data.Odbc.OdbcTransaction BeginTransaction (System.Data.IsolationLevel isolevel);
override this.BeginTransaction : System.Data.IsolationLevel -> System.Data.Odbc.OdbcTransaction
member this.BeginTransaction : System.Data.IsolationLevel -> System.Data.Odbc.OdbcTransaction
Public Function BeginTransaction (isolevel As IsolationLevel) As OdbcTransaction

Parameters

isolevel
IsolationLevel

The transaction isolation level for this connection. If you do not specify an isolation level, the default isolation level for the driver is used.

Returns

An object representing the new transaction.

Exceptions

A transaction is currently active. Parallel transactions are not supported.

Examples

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

public static void ExecuteTransaction(string connectionString)
{
    using (OdbcConnection connection =
               new OdbcConnection(connectionString))
    {
        OdbcCommand command = new OdbcCommand();
        OdbcTransaction transaction = null;

        // Set the Connection to the new OdbcConnection.
        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 OdbcConnection(connectionString)
        Dim command As New OdbcCommand()
        Dim transaction As OdbcTransaction

        ' Set the Connection to the new OdbcConnection.
        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

To commit or roll back the transaction, you must explicitly use the Commit or Rollback methods.

To make sure that the .NET Framework Data Provider for ODBC transaction management model performs correctly, avoid using other transaction management models, such as those provided by the data source.

See also

Applies to