SqlCeTransaction.Rollback Method

Reverta uma transação de um estado pendente.

Namespace: System.Data.SqlServerCe
Assembly: System.Data.SqlServerCe (em system.data.sqlserverce.dll)

Sintaxe

'Declaração
Public Overrides Sub Rollback

public override void Rollback ()

public:
virtual void Rollback () override

public void Rollback ()

public override function Rollback ()

Exceções

Tipo de exceção	Condição
Exception	Erro ao tentar confirmar a transação.
InvalidOperationException	A transação já foi confirmada ou revertida. - ou - A conexão foi desfeita.

Comentários

A transação poderá ser revertida somente de um estado pendente (depois que BeginTransaction foi chamado, mas antes de Commit ser chamado).

Exemplo

O exemplo a seguir cria uma SqlCeConnection e uma SqlCeTransaction. Ele também demonstra como usar os métodos BeginTransaction, a Commit e Rollback.

Dim conn As New SqlCeConnection("Data Source = AdventureWorks.sdf;")
conn.Open()

' Start a local transaction; SQL Mobile supports the following 
' isolation levels: ReadCommitted, RepeatableRead, Serializable
'
Dim tx As SqlCeTransaction = conn.BeginTransaction(IsolationLevel.ReadCommitted)

' By default, commands run in auto-commit mode; 
'
Dim cmd1 As SqlCeCommand = conn.CreateCommand()

' You may create multiple commands on the same connection
'
Dim cmd2 As SqlCeCommand = conn.CreateCommand()

' To enlist a command in a transaction, set the Transaction property
'
cmd1.Transaction = tx

Try
    cmd1.CommandText = "INSERT INTO FactSalesQuota " & _
        "(EmployeeKey, TimeKey, SalesAmountQuota) " & _
        "VALUES (2, 1158, 150000.00)"

    cmd1.ExecuteNonQuery()

    ' Auto-commited because cmd2 is not enlisted in a transaction
    '
    cmd2.CommandText = "INSERT INTO FactSalesQuota " & _
        "(EmployeeKey, TimeKey, SalesAmountQuota) " & _
        "VALUES (3, 1157, 15000.00)"

    cmd2.ExecuteNonQuery()

    ' Commit the changes to disk if everything above succeeded;
    ' Use Deferred mode for optimal performance; the changes will 
    ' be flashed to disk within the timespan specified in the 
    ' ConnectionString 'FLUSH INTERVAL' property; 
    '
    tx.Commit(CommitMode.Deferred)

    ' Alternatively, you could use:
    ' tx.Commit(CommitMode.Immediate);
    '
    ' or use default (Deferred) commit mode:
    ' tx.Commit()

Catch e As Exception
    ' Handle errors here
    '
    tx.Rollback()
Finally
    conn.Close()
End Try

SqlCeConnection conn = new SqlCeConnection("Data Source = AdventureWorks.sdf;");
conn.Open();

// Start a local transaction; SQL Mobile supports the following 
// isolation levels: ReadCommitted, RepeatableRead, Serializable
//
SqlCeTransaction tx = conn.BeginTransaction(IsolationLevel.ReadCommitted);

// By default, commands run in auto-commit mode; 
//
SqlCeCommand cmd1 = conn.CreateCommand();

// You may create multiple commands on the same connection
//
SqlCeCommand cmd2 = conn.CreateCommand();

// To enlist a command in a transaction, set the Transaction property
//
cmd1.Transaction = tx;

try
{
    cmd1.CommandText = "INSERT INTO FactSalesQuota " +
        "(EmployeeKey, TimeKey, SalesAmountQuota) " +
        "VALUES (2, 1158, 150000.00)";

    cmd1.ExecuteNonQuery();

    // Auto-commited because cmd2 is not enlisted in a transaction
    //
    cmd2.CommandText = "INSERT INTO FactSalesQuota " +
        "(EmployeeKey, TimeKey, SalesAmountQuota) " +
        "VALUES (3, 1157, 15000.00)";

    cmd2.ExecuteNonQuery();

    // Commit the changes to disk if everything above succeeded;
    // Use Deferred mode for optimal performance; the changes will 
    // be flashed to disk within the timespan specified in the 
    // ConnectionString 'FLUSH INTERVAL' property; 
    //
    tx.Commit(CommitMode.Deferred);

    // Alternatively, you could use:
    // tx.Commit(CommitMode.Immediate);
    //
    // or use default (Deferred) commit mode:
    // tx.Commit()
}
catch (Exception)
{
    // Handle errors here
    //
    tx.Rollback();
}
finally
{
    conn.Close();
}

Segurança de thread

Quaisquer membros estáticos públicos (compartilhados no Microsoft Visual Basic) desse tipo são thread safe. Não há garantia de que qualquer membro de instância seja thread safe.

Plataformas

Plataformas de desenvolvimento

Windows Vista, Windows Mobile 5.0, Windows XP Professional with Service Pack 2 (SP2), Windows Server 2003, Windows Mobile 2003 for Pocket PC, Windows CE 5.0
Informações de versão
.NET Framework e NET Compact Framework
Com suporte no 3.5
.NET Framework
Com suporte no 3.0
.NET Compact Framework e .Net Framework
Com suporte no 2.0

Consulte também

Referência

SqlCeTransaction Class
SqlCeTransaction Members
System.Data.SqlServerCe Namespace
SqlCeTransaction.Commit Method
SqlCeConnection.BeginTransaction Method