如何在一个LINQ请求中使用两个不同的数据上下文? [英] How can I use two different data contexts in one LINQ request?

问题描述

接下来有人可以帮助我吗:如何在一个LINQ请求中使用两个不同的数据上下文?

Can anybody help me with next: how can I use two different data contexts in one LINQ request?

using (var db = new DataMapDataContext(Connection))
        {    
            using (var dbAdd = new DataMapDataContext(ConnectionAdd))
            {
                return (from i in dbAdd.ITEMs
                        join p in db.U_OTT_PINs on i.ITEMNO equals p.PIN_CODE
                        where p.PIN_TYPE == Utils.PinItem
                        select ...
            }
        }

有可能吗?

更新:

我解决了我的问题，但没有使用其他数据上下文:

I resolved my issue, but not with different data contexts:

        var listPinnedItems = new List<string>();
        using (var db = new DataMapDataContext(Connection))
        {
            listPinnedItems = (from lpi in db.U_OTT_PINs
                               where lpi.PIN_TYPE == Utils.PinItem
                               select lpi.PIN_CODE).ToList();
        }

        using (var dbAdd = new DataMapDataContext(ConnectionAdd))
        {
            return (from i in dbAdd.ITEMs
                    where listPinnedItems.Contains(i.ITEMNO) 
                    ...

推荐答案

我不这么认为-这两个不同的上下文可能涉及同一数据库中的不同事务，甚至与完全不同的数据库实例进行通信.它将如何构造SQL使其在两者之间起作用?

I don't believe so - these two different contexts could be involved in different transactions in the same database, or even talking to completely different database instances. How would it construct SQL to work across the two?

如果您可以解释您要做什么，我们也许可以为您提供更多帮助.

If you could explain what you're trying to do, we may be able to help you more.

这篇关于如何在一个LINQ请求中使用两个不同的数据上下文?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！