SqlCeConnection.BeginTransaction 方法 (IsolationLevel)
以当前的 IsolationLevel 值开始数据库事务。
命名空间: System.Data.SqlServerCe
程序集: System.Data.SqlServerCe(在 system.data.sqlserverce.dll 中)
语法
声明
Public Function BeginTransaction ( _
isolationLevel As IsolationLevel _
) As SqlCeTransaction
用法
Dim instance As SqlCeConnection
Dim isolationLevel As IsolationLevel
Dim returnValue As SqlCeTransaction
returnValue = instance.BeginTransaction(isolationLevel)
public SqlCeTransaction BeginTransaction (
IsolationLevel isolationLevel
)
public:
SqlCeTransaction^ BeginTransaction (
IsolationLevel isolationLevel
)
public SqlCeTransaction BeginTransaction (
IsolationLevel isolationLevel
)
public function BeginTransaction (
isolationLevel : IsolationLevel
) : SqlCeTransaction
不适用。
参数
- isolationLevel
该连接的事务隔离级别。
返回值
表示新事务的对象。
备注
必须使用 Commit 或 Rollback 方法显式提交或回滚事务。
示例
下面的示例创建一个 SqlCeConnection 和一个 SqlCeTransaction,然后阐释如何使用 BeginTransaction、Commit 和 Rollback 方法。
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();
}
平台
Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
Windows Vista、Microsoft Windows XP SP2 和 Windows Server 2003 SP1 支持 Microsoft .NET Framework 3.0。
版本信息
.NET Framework
受以下版本支持:3.0
.NET Compact Framework
受以下版本支持:2.0、1.0
请参见
参考
SqlCeConnection 类
SqlCeConnection 成员
System.Data.SqlServerCe 命名空间
Commit
Rollback