在数据读取错误的实体框架 [英] Error in data reader in entity framework

问题描述

我在执行这个简单的查询与实体框架

I'm executing this simple query with Entity Framework

db.Database.SqlQuery<string>("SELECT * FROM hospital");

不过，我得到这个错误：

But I got this error:

数据读取器有一个以上的域。多领域不适用于电火花加工的原始或枚举类型。

The data reader has more than one field. Multiple fields are not valid for EDM primitive or enumeration types.

这可能是什么问题？

推荐答案

这将看到什么医院表看起来像，但假设一些简单的像医院由HospitalId和HospitalName，那么你有一对夫妇的选择是有用的。

It would be useful to see what the hospital table looks like but assuming something simple like hospital consists of HospitalId and HospitalName then you have a couple of choices.

db.Database.SqlQuery<IEnumerable<string>>("SELECT hospitalName FROM hospital"); //would work if all you're trying to do is get the Name

db.Database.SqlQuery<MyEntity>("SELECT * FROM hospital"); //where you define MyEntity as the same structure as the table would work

db.Database.SqlQuery<IEnumerable<Tuple<int, string>>>("SELECT * FROM hospital"); // would theoretically work although I haven't tried it.  Where the Tuple items would have to match the database types in order.  I.e. if field 1 is an int and field 2 is a string then Tuple<int,string>

基本上错误是code不知道如何东西院的结构转换为字符串

Basically the error is the code doesn't know how to stuff the structure of hospital into a string

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