SqlCeConnection.BeginTransaction メソッド
データベース トランザクションを開始します。
名前空間: System.Data.SqlServerCe
アセンブリ: System.Data.SqlServerCe (System.Data.SqlServerCe.dll)
構文
'宣言
Public Function BeginTransaction As SqlCeTransaction
'使用
Dim instance As SqlCeConnection
Dim returnValue As SqlCeTransaction
returnValue = instance.BeginTransaction()
public SqlCeTransaction BeginTransaction()
public:
SqlCeTransaction^ BeginTransaction()
member BeginTransaction : unit -> SqlCeTransaction
public function BeginTransaction() : SqlCeTransaction
戻り値
型: System.Data.SqlServerCe.SqlCeTransaction
新しいトランザクションを表すオブジェクト。
説明
トランザクションは、Commit メソッドまたは Rollback メソッドを使用して、明示的にコミットまたはロールバックする必要があります。
使用例
SqlCeConnection と SqlCeTransaction を作成し、BeginTransaction、Commit、および Rollback の各メソッドの使用方法を示す例を次に示します。
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 ('Decker', 'Barbara')"
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 ('Decker', 'Barbara')";
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();
}