Entity Framework中的批量提交与事务处理【转载】

Posted on 2011-09-13 21:51 itcfj 阅读(955) 评论(2) 收藏举报

        testModel.testEntities1 test = new testModel.testEntities1();
        //test.Connection.Open();
        //test.ExecuteStoreCommand("insert into userinfo (id,username,password) values(44554,'aaa','dddd')");
        //System.Data.Common.DbTransaction trans = test.Connection.BeginTransaction();
        // UserInfo user = new UserInfo { id = "111111111", password = "a", username = "a" };
        UserInfo user1 = new UserInfo { id = "111144111", password = "ddd", username = "地对地导弹" };
        Email em = new Email { emal = "dd", userid = "111111111", id = "dd" };
        // test.AddObject("UserInfo", user);
        test.AddObject("Email", em);
        test.AddObject("UserInfo", user1);
        test.SaveChanges().ToString();//对相同表，还是不相同表操作都是事务
        //trans.Commit();

        //testModel.testEntities1 test = new testModel.testEntities1();
        //test.Connection.Open();
        //test.ExecuteStoreCommand("insert into userinfo (id,username,password) values(44554,'aaa','dddd')");
        //System.Data.Common.DbTransaction trans = test.Connection.BeginTransaction();
        //UserInfo user = new UserInfo { id = "23333332", password = "ddd", username = "dddd" };
        //test.AddObject("UserInfo", user);
        //Response.Write(test.SaveChanges().ToString());
        //trans.Commit();

Entity Framework中的批量提交与事务处理

在Entity Framework 中使用SaveChanges()是很频繁的，单次修改或删除数据后调用SaveChanges()返回影响记录数。

要使用批量修改或者批量删除数据，就需要SaveChanges(false)+AcceptAllChanges()方法了。

SaveChanges(false) 只是通知EF需要对数据库执行的操作，在内存中是属于挂起状态，在必要的时候是可以撤销的，比如AcceptAllChange()提交为真正成功，EF将撤销SaveChanges(false)的操作。

而在处理分布式事务操作的时候，就有必要使用TransactionScope 来处理了，很多时候我们会这样写：

using (TransactionScope scope = new TransactionScope())
{
    //Do something with context1
    //Do something with context2

    //Save and discard changes
    context1.SaveChanges();

    //Save and discard changes
    context2.SaveChanges();

    //if we get here things are looking good.
    scope.Complete();
}

但是这样写是有风险的，假

如context1.SaveChanges()成功了，context2.SaveChanges()却是有问题的，我们在scope.Complete()提交事务的时候就会终止，而Context1已经成功执行了

这可能不一定符合我们的需要。如果我们需要 context1、context2要不同时执行成功，要不都不成功，我们需要对代码作小小的调整，如用下面的代码：

using (TransactionScope scope = new TransactionScope())
{
    //Do something with context1
    //Do something with context2

    //Save Changes but don't discard yet
    context1.SaveChanges(false);

    //Save Changes but don't discard yet
    context2.SaveChanges(false);

    //if we get here things are looking good.
    scope.Complete();
    context1.AcceptAllChanges();
    context2.AcceptAllChanges();

}