Rollback Method
Rolls back a transaction from a pending state.
Namespace: System.Data.SqlServerCe
Assembly: System.Data.SqlServerCe (in System.Data.SqlServerCe.dll)
Syntax
'Declaration
Public Overrides Sub Rollback
'Usage
Dim instance As SqlCeTransaction
instance.Rollback()
public override void Rollback()
public:
virtual void Rollback() override
abstract Rollback : unit -> unit
override Rollback : unit -> unit
public override function Rollback()
Implements
IDbTransaction. . :: . .Rollback() () () ()
Exceptions
| Exception | Condition |
|---|---|
| Exception | An error occurred while trying to commit the transaction. |
| InvalidOperationException | The transaction has already been committed or rolled back. -or- The connection is broken. |
Remarks
The transaction can only be rolled back from a pending state (after BeginTransaction has been called, but before Commit is called).
Examples
The following example creates a SqlCeConnection and a SqlCeTransaction. It also demonstrates how to use the BeginTransaction, a Commit, and Rollback methods.
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();
}