SqlCeConnection.BeginTransaction Method (IsolationLevel)

Article
01/14/2011

Commence une transaction de base de données avec la valeur IsolationLevel actuelle.

Espace de noms: System.Data.SqlServerCe
Assembly: System.Data.SqlServerCe (dans system.data.sqlserverce.dll)

Syntaxe

'Déclaration
Public Function BeginTransaction ( _
    isolationLevel As IsolationLevel _
) As SqlCeTransaction

public SqlCeTransaction BeginTransaction (
    IsolationLevel isolationLevel
)

public:
SqlCeTransaction^ BeginTransaction (
    IsolationLevel isolationLevel
)

public SqlCeTransaction BeginTransaction (
    IsolationLevel isolationLevel
)

public function BeginTransaction (
    isolationLevel : IsolationLevel
) : SqlCeTransaction

Paramètres

isolationLevel
Niveau d'isolation des transactions pour cette connexion.

Valeur de retour

Objet représentant la nouvelle transaction.

Remarques

Vous devez valider ou restaurer explicitement la transaction à l'aide de la méthode Commit ou Rollback.

Exemple

L'exemple suivant crée SqlCeConnection et SqlCeTransaction puis montre comment utiliser les méthodes BeginTransaction, Commit et 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();
}

Sécurité des threads

Tout membre statique public (Partagé dans Microsoft Visual Basic) de ce type sont thread-safe. Tous les membres de l'instance ne sont pas garantis comme sûrs.

Plateformes

Plateformes de développement

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
Informations sur la version
.NET Framework et NET Compact Framework
Pris en charge dans 3.5
.NET Framework
Pris en charge dans 3.0
.NET Compact Framework et .Net Framework
Pris en charge dans 2.0

Voir aussi

Référence

SqlCeConnection Class
SqlCeConnection Members
System.Data.SqlServerCe Namespace
Commit
Rollback

Autres ressources

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