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实体框架4.1的SQL``插入''语法

sql

我有一个简单的问题,即与“ not in” SQL等效项有关的实体框架语法。本质上,我想将以下SQL语法转换为Entity Framework语法:

select  ID
from    dbo.List
where   ID not in (list of IDs)

这是我用于查找单个记录的方法:

public static List GetLists(int id)
{
    using (dbInstance db = new dbInstance())
    {
        return db.Lists.Where(m => m.ID == id);
    }
}

这是我要用于此的伪方法:

public static List<List> GetLists(List<int> listIDs)
{
    using (dbInstance db = new dbInstance())
    {
        return db.Lists.Where(**** What Goes Here ****).ToList();
    }
}

谁能给我指点一下Where条款区域的内容吗?我阅读了一些有关此的论坛,并提到了使用.Contains()或的情况.Any(),但是没有一个例子非常合适。


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2021-05-10

共1个答案

admin

快去…

public static List<List> GetLists(List<int> listIDs)
{
    using (dbInstance db = new dbInstance())
    {
        // Use this one to return List where IS NOT IN the provided listIDs
        return db.Lists.Where(x => !listIDs.Contains(x.ID)).ToList();

        // Or use this one to return List where IS IN the provided listIDs
        return db.Lists.Where(x => listIDs.Contains(x.ID)).ToList();
    }
}

这些将大致变成以下数据库查询:

SELECT [Extent1].*
FROM [dbo].[List] AS [Extent1]
WHERE  NOT ([Extent1].[ID] IN (<your,list,of,ids>))

或者

SELECT [Extent1].*
FROM [dbo].[List] AS [Extent1]
WHERE  [Extent1].[ID] IN (<your,list,of,ids>)

分别。

2021-05-10