在Linq to Sql中使用記錄的時間戳進行檢測管理并發更新時的沖突

try
{
LinqToSqlDemoDataContext dataContext = new LinqToSqlDemoDataContext();
Order order1 = dataContext.Orders.Single(o => o.OrderID == 1);
Order order2 = dataContext.Orders.Single(o => o.OrderID == 2);
Order order3 = dataContext.Orders.Single(o => o.OrderID == 3);
Console.WriteLine('Order 1: ' + order1.Introduction);
Console.WriteLine('Order 2: ' + order2.Introduction);
Console.WriteLine('Order 3: ' + order3.Introduction);
Console.WriteLine();
order1.Introduction = 'Order 1 modified.';
order2.Introduction = 'Order 2 modified.';
order3.Introduction = 'Order 3 modified.';
dataContext.Log = Console.Out;
// 在下面的語句上設置一個斷點
dataContext.SubmitChanges();
}
catch (ChangeConflictException e)
{
Console.WriteLine('---------- ' + e.Message + ' ----------');
}
LinqToSqlDemoDataContext db = new LinqToSqlDemoDataContext();
Order o1 = db.Orders.Single(o =＞ o.OrderID == 1);
Order o2 = db.Orders.Single(o =＞ o.OrderID == 2);
Order o3 = db.Orders.Single(o =＞ o.OrderID == 3);
Console.WriteLine('Order 1: ' + o1.Introduction);
Console.WriteLine('Order 2: ' + o2.Introduction);
Console.WriteLine('Order 3: ' + o3.Introduction);
Console.ReadLine();

OrderID Name Introduction record_version
1 Order 1 This is order 1 ＜Binary data＞
2 Order 2 This is order 2 ＜Binary data＞
3 Order 3 This is order 3 ＜Binary data＞

UPDATE Order SET OrderID = "New Order 2" WHERE OrderID = 2

Order 1: This is order 1
Order 2: This is order 2
Order 3: This is order 3
UPDATE [dbo].[Order]
SET [Introduction] = @p2
WHERE ([OrderID] = @p0) AND ([record_version] = @p1)
SELECT [t1].[record_version]
FROM [dbo].[Order] AS [t1]
WHERE ((@@ROWCOUNT) ＞ 0) AND ([t1].[OrderID] = @p3)
-- @p0: Input Int (Size = 0; Prec = 0; Scale = 0) [1]
-- @p1: Input Timestamp (Size = 8; Prec = 0; Scale = 0) [SqlBinary(8)]
-- @p2: Input NVarChar (Size = 26; Prec = 0; Scale = 0) [Order 1 modified.]
-- @p3: Input Int (Size = 0; Prec = 0; Scale = 0) [1]
-- Context: SqlProvider(Sql2005) Model: AttributedMetaModel Build: 3.5.21022.8

UPDATE [dbo].[Order]
SET [Introduction] = @p2
WHERE ([OrderID] = @p0) AND ([record_version] = @p1)
SELECT [t1].[record_version]
FROM [dbo].[Order] AS [t1]
WHERE ((@@ROWCOUNT) ＞ 0) AND ([t1].[OrderID] = @p3)
-- @p0: Input Int (Size = 0; Prec = 0; Scale = 0) [2]
-- @p1: Input Timestamp (Size = 8; Prec = 0; Scale = 0) [SqlBinary(8)]
-- @p2: Input NVarChar (Size = 26; Prec = 0; Scale = 0) [Order 2 modified.]
-- @p3: Input Int (Size = 0; Prec = 0; Scale = 0) [2]
-- Context: SqlProvider(Sql2005) Model: AttributedMetaModel Build: 3.5.21022.8

---------- 1 of 2 updates failed. ----------
Order 1: This is order 1
Order 2: This is order 2
Order 3: This is order 3