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SqlTransaction.Rollback Method

Definition

Rolls back a transaction from a pending state.

Overloads

Rollback()

Rolls back a transaction from a pending state.

Rollback(String)

Rolls back a transaction from a pending state, and specifies the transaction or savepoint name.

Rollback()

Rolls back a transaction from a pending state.

public:
 override void Rollback();
public:
 virtual void Rollback();
public override void Rollback ();
public void Rollback ();
override this.Rollback : unit -> unit
abstract member Rollback : unit -> unit
override this.Rollback : unit -> unit
Public Overrides Sub Rollback ()
Public Sub Rollback ()

Implements

Exceptions

An error occurred while trying to commit the transaction.

The transaction has already been committed or rolled back.

-or-

The connection is broken.

Examples

The following example creates a SqlConnection and a SqlTransaction. It also demonstrates how to use the BeginTransaction, Commit, and Rollback methods. The transaction is rolled back on any error. Try/Catch error handling is used to handle any errors when attempting to commit or roll back the transaction.

private static void ExecuteSqlTransaction(string connectionString)
{
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
        connection.Open();

        SqlCommand command = connection.CreateCommand();
        SqlTransaction transaction;

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

        // Must assign both transaction object and connection
        // to Command object for a pending local transaction
        command.Connection = connection;
        command.Transaction = transaction;

        try
        {
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')";
            command.ExecuteNonQuery();
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')";
            command.ExecuteNonQuery();

            // Attempt to commit the transaction.
            transaction.Commit();
            Console.WriteLine("Both records are written to database.");
        }
        catch (Exception ex)
        {
            Console.WriteLine("Commit Exception Type: {0}", ex.GetType());
            Console.WriteLine("  Message: {0}", ex.Message);

            // Attempt to roll back the transaction.
            try
            {
                transaction.Rollback();
            }
            catch (Exception ex2)
            {
                // This catch block will handle any errors that may have occurred
                // on the server that would cause the rollback to fail, such as
                // a closed connection.
                Console.WriteLine("Rollback Exception Type: {0}", ex2.GetType());
                Console.WriteLine("  Message: {0}", ex2.Message);
            }
        }
    }
}
Private Sub ExecuteSqlTransaction(ByVal connectionString As String)
    Using connection As New SqlConnection(connectionString)
        connection.Open()

        Dim command As SqlCommand = connection.CreateCommand()
        Dim transaction As SqlTransaction

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

        ' Must assign both transaction object and connection
        ' to Command object for a pending local transaction.
        command.Connection = connection
        command.Transaction = transaction

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

            command.ExecuteNonQuery()

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

        Catch ex As Exception
            Console.WriteLine("Commit Exception Type: {0}", ex.GetType())
            Console.WriteLine("  Message: {0}", ex.Message)

            ' Attempt to roll back the transaction.
            Try
                transaction.Rollback()

            Catch ex2 As Exception
                ' This catch block will handle any errors that may have occurred
                ' on the server that would cause the rollback to fail, such as
                ' a closed connection.
                Console.WriteLine("Rollback Exception Type: {0}", ex2.GetType())
                Console.WriteLine("  Message: {0}", ex2.Message)
            End Try
        End Try
    End Using
End Sub

Remarks

The Rollback method is equivalent to the Transact-SQL ROLLBACK TRANSACTION statement. For more information, see ROLLBACK TRANSACTION (Transact-SQL) .

The transaction can only be rolled back from a pending state (after BeginTransaction has been called, but before Commit is called). The transaction is rolled back in the event it is disposed before Commit or Rollback is called.

Note

Try/Catch exception handling should always be used when rolling back a transaction. A Rollback generates an InvalidOperationException if the connection is terminated or if the transaction has already been rolled back on the server.

For more information on SQL Server transactions, see Transactions (Transact-SQL).

See also

Applies to

Rollback(String)

Rolls back a transaction from a pending state, and specifies the transaction or savepoint name.

public:
 void Rollback(System::String ^ transactionName);
public void Rollback (string transactionName);
override this.Rollback : string -> unit
member this.Rollback : string -> unit
Public Sub Rollback (transactionName As String)

Parameters

transactionName
String

The name of the transaction to roll back, or the savepoint to which to roll back.

Exceptions

No transaction name was specified.

The transaction has already been committed or rolled back.

-or-

The connection is broken.

Examples

The following example creates a SqlConnection and a SqlTransaction. It also demonstrates how to use the BeginTransaction, Commit, and Rollback methods. The transaction is rolled back on any error. Try/Catch error handling is used to handle any errors when attempting to commit or roll back the transaction.

private static void ExecuteSqlTransaction(string connectionString)
{
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
        connection.Open();

        SqlCommand command = connection.CreateCommand();
        SqlTransaction transaction;

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

        // Must assign both transaction object and connection
        // to Command object for a pending local transaction
        command.Connection = connection;
        command.Transaction = transaction;

        try
        {
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')";
            command.ExecuteNonQuery();
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')";
            command.ExecuteNonQuery();

            // Attempt to commit the transaction.
            transaction.Commit();
            Console.WriteLine("Both records are written to database.");
        }
        catch (Exception ex)
        {
            Console.WriteLine("Commit Exception Type: {0}", ex.GetType());
            Console.WriteLine("  Message: {0}", ex.Message);

            // Attempt to roll back the transaction.
            try
            {
                transaction.Rollback("SampleTransaction");
            }
            catch (Exception ex2)
            {
                // This catch block will handle any errors that may have occurred
                // on the server that would cause the rollback to fail, such as
                // a closed connection.
                Console.WriteLine("Rollback Exception Type: {0}", ex2.GetType());
                Console.WriteLine("  Message: {0}", ex2.Message);
            }
        }
    }
}
Private Sub ExecuteSqlTransaction(ByVal connectionString As String)
    Using connection As New SqlConnection(connectionString)
        connection.Open()

        Dim command As SqlCommand = connection.CreateCommand()
        Dim transaction As SqlTransaction

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

        ' Must assign both transaction object and connection
        ' to Command object for a pending local transaction.
        command.Connection = connection
        command.Transaction = transaction

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

            command.ExecuteNonQuery()

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

        Catch ex As Exception
            Console.WriteLine("Exception Type: {0}", ex.GetType())
            Console.WriteLine("  Message: {0}", ex.Message)

            ' Attempt to roll back the transaction.
            Try
                transaction.Rollback("SampleTransaction")

            Catch ex2 As Exception
                ' This catch block will handle any errors that may have occurred
                ' on the server that would cause the rollback to fail, such as
                ' a closed connection.
                Console.WriteLine("Rollback Exception Type: {0}", ex2.GetType())
                Console.WriteLine("  Message: {0}", ex2.Message)
            End Try
        End Try
    End Using
End Sub

Remarks

The Rollback method is equivalent to the Transact-SQL ROLLBACK TRANSACTION statement. For more information, see Transactions (Transact-SQL).

The transaction can only be rolled back from a pending state (after BeginTransaction has been called, but before Commit is called). The transaction is rolled back if it is disposed before Commit or Rollback is called.

Note

Try/Catch exception handling should always be used when rolling back a transaction. A Rollback generates an InvalidOperationException if the connection is terminated or if the transaction has already been rolled back on the server.

For more information on SQL Server transactions, see Transactions (Transact-SQL).

See also

Applies to