Question

On my DBMS, I have two tables having one-to-many relationship (A <- B). At the first running, I retrieved some records of A (including B) like this:

var lst = from a in ctx.As.Include("Bs") select a;

So, everything is ok. But a few minutes later, I want to get them again because they could be changed on other apps.

我试着用

ctx.Refresh(RefreshMode.StoreWins, lst);

When I do that, the only things are refreshed is object from B, not A. Therefore, I must do another step like:

foreach (var a in lst) {
    ctx.Refresh(RefreshMode.StoreWins, a.Bs);
}

如果我没有将 Bs 包含在linq 语句中, 那么使用 Load 方法, 而不是 refresh

这里的问题是调用Refresh 或 Load 太多倍,也许会降低性能。我如何在不打电话这么多的情况下从数据库存储处重新装入它们?

谢谢!

Answer 1

但几分钟后...

背景是工作单位和工作单位通常不会花几分钟时间,所以您问题的基本答案是创造新的背景并再次执行查询。

如果您真的认为您的上下文必须持续如此长的时间(我怀疑它必须持续如此长的时间, 因为在这种情况下您不想覆盖本地更改), 您可以尝试 :

ctx.As.MergeOption = MergeOption.OverwriteChanges;
ctx.Bs.MergeOption = MergeOption.OverwriteChanges;
var lst = from a in ctx.As.Include("Bs") select a;

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