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SqlCeConnection.BeginTransaction Method ()

Begins a database transaction.

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

Syntax

'Declaration
Public Function BeginTransaction As SqlCeTransaction
'Usage
Dim instance As SqlCeConnection
Dim returnValue As SqlCeTransaction

returnValue = instance.BeginTransaction
public SqlCeTransaction BeginTransaction ()
public:
SqlCeTransaction^ BeginTransaction ()
public SqlCeTransaction BeginTransaction ()
public function BeginTransaction () : SqlCeTransaction
Not applicable.

Return Value

An object representing the new transaction.

Remarks

You must explicitly commit or roll back the transaction using the Commit or Rollback method.

Example

The following example creates a SqlCeConnection and a SqlCeTransaction, and then demonstrates how to use the BeginTransaction, Commit, and Rollback methods.

Dim conn As New SqlCeConnection("Data Source = MyDatabase.sdf; Password ='<pwd>'")
conn.Open()

' Start a local transaction
'
Dim tx As SqlCeTransaction = conn.BeginTransaction()

' 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 Shippers ([Company Name]) VALUES ('Northwind Traders')"
    cmd1.ExecuteNonQuery()

    ' Auto-commited because cmd2 is not enlisted in a transaction
    '
    cmd2.CommandText = "INSERT INTO Employees ([Last Name], [First Name]) VALUES ('Nancy', 'Smith')"
    cmd2.ExecuteNonQuery()

    ' This will cause referential constraint violation
    '
    cmd1.CommandText = "DELETE FROM Products WHERE [Product ID] = 1"
    cmd1.ExecuteNonQuery()

    ' Commit the changes to disk if everything above succeeded
    '
    tx.Commit()
Catch
    tx.Rollback()
Finally
    conn.Close()
End Try
SqlCeConnection conn = new SqlCeConnection("Data Source = MyDatabase.sdf; Password ='<pwd>'");
conn.Open();

// Start a local transaction
//
SqlCeTransaction tx = conn.BeginTransaction();

// 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 Shippers ([Company Name]) VALUES ('Northwind Traders')";
    cmd1.ExecuteNonQuery();

    // Auto-commited because cmd2 is not enlisted in a transaction
    //
    cmd2.CommandText = "INSERT INTO Employees ([Last Name], [First Name]) VALUES ('Nancy', 'Smith')";
    cmd2.ExecuteNonQuery();

    // This will cause referential constraint violation
    //
    cmd1.CommandText = "DELETE FROM Products WHERE [Product ID] = 1";
    cmd1.ExecuteNonQuery();

    // Commit the changes to disk if everything above succeeded
    //
    tx.Commit();
}
catch (Exception)
{
    tx.Rollback();
}
finally
{
    conn.Close();
}

Platforms

Windows CE, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows XP Professional x64 Edition, Windows XP SP2

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

Version Information

.NET Framework

Supported in: 3.0

.NET Compact Framework

Supported in: 2.0, 1.0

See Also

Reference

SqlCeConnection Class
SqlCeConnection Members
System.Data.SqlServerCe Namespace