实体框架6 context.Database.SqlQuery <bool>

Question

可能是一个很好的解决办法。

我需要做一个原始的SQL数据库查询：

var blnOrders = (bool)db.Database.SqlQuery<bool>(@"SELECT 
    CASE WHEN (EXISTS (SELECT 
     1 AS [C1] 
     FROM [dbo].[Orders] AS [Extent1] WITH (TABLOCKX, HOLDLOCK) 
     WHERE [Extent1].[OrderNumber] IS NOT NULL 
    )) THEN cast(1 as bit) WHEN (NOT EXISTS (SELECT 
     1 AS [C1] 
     FROM [dbo].[Orders] AS [Extent2] WITH (TABLOCKX, HOLDLOCK) 
     WHERE [Extent2].[OrderNumber] IS NOT NULL 
    )) THEN cast(0 as bit) END AS [C1] 
    FROM (SELECT 1 AS X) AS [SingleRowTable1]") 

一个DbRawSqlQuery<bool>从此返回。试图将其转换为bool，然后使用变量使我有以下错误：

Cannot implicitly convert type 'System.Data.Entity.Infrastructure.DbRawSqlQuery<bool>' to 'bool' 

我不知道我做错了什么？我以为你可以把它投到bool？

检查了文档here，但仅有一个使用SqlQuery<string>的示例。

Answer 1

拆下（布尔）作为伊赫桑告诉你，然后

var res = await blnOrders.SingleAsync();