MSSQL错误'底层提供程序在Open上失败“ [英] MSSQL Error 'The underlying provider failed on Open'

问题描述

我正在使用 .mdf 连接到数据库和 entityClient 。现在我想更改连接字符串，以便不会有 .mdf 文件。

I was using an .mdf for connecting to a database and entityClient. Now I want to change the connection string so that there will be no .mdf file.

以下 connectionString 正确？

<connectionStrings>
   <!--<add name="conString" connectionString="metadata=res://*/conString.csdl|res://*/conString.ssdl|res://*/conString.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=.\SQL2008;AttachDbFilename=|DataDirectory|\NData.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True;MultipleActiveResultSets=True&quot;" providerName="System.Data.EntityClient" />-->
   <add name="conString" connectionString="metadata=res://*/conString.csdl|res://*/conString.ssdl|res://*/conString.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=.\SQL2008;Initial Catalog=NData;Integrated Security=True;Connect Timeout=30;User Instance=True;MultipleActiveResultSets=True&quot;" providerName="System.Data.EntityClient" />

因为我总是收到错误：

底层提供程序在Open上失败

The underlying provider failed on Open

推荐答案

我有这个错误，并找到了一些解决方案：

I had this error and found a few solutions:

查看你的连接字符串，看起来很有效。我发现这篇博文，这里的问题他们使用的是集成安全性 。如果您在IIS上运行，则您的IIS用户需要访问数据库。

Looking at your connection string, it looks valid. I found this blog post, the problem here is that they were using Integrated Security. If you are running on IIS, your IIS user needs access to the database.

如果您使用实体框架 与事务，实体框架自动打开和关闭与每个数据库调用的连接。因此，当使用事务时，您尝试通过多个连接传播事务。这可以升级到 MSDTC 。

If you are using Entity Framework with Transactions, Entity Framework automatically opens and closes a connection with each database call. So when using transactions, you are attempting to spread a transaction out over multiple connections. This elevates to MSDTC.

有关详细信息，请参阅此参考。）

将我的代码修改为以下修正：

Changing my code to the following fixed it:

using (DatabaseEntities context = new DatabaseEntities())
{
    context.Connection.Open();
    // the rest
}

这篇关于MSSQL错误'底层提供程序在Open上失败“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！