将此 SQL 语句转换为 LINQ

发布于 2024-11-07 22:49:30 字数 582 浏览 0 评论 0原文

我对 linq 很陌生，在 LINQ 中高效编写此查询时遇到一些困难。

SELECT ID, UniqueID, RouteHeaderID, RouteObjectState, OriginalRouteUniqueID
FROM  dbo.MeterReadingOrderERPRouteCreateResponses
WHERE (ID NOT IN (SELECT MeterReadingOrderERPRouteCreateResponseID
                  FROM  dbo.Tasks
                  WHERE (TaskType = 'MeterReading')))

有什么帮助吗？我尝试过以下解决方案：你会如何做使用 LINQ 进行“不在”查询？但出现以下错误：无法创建“TaskManager.Models.Task”类型的常量值。此上下文中仅支持原始类型（“例如 Int32、String 和 Guid”）。

原文

i am quite new to linq and i am having some difficulties writing this query efficiently in LINQ.

SELECT ID, UniqueID, RouteHeaderID, RouteObjectState, OriginalRouteUniqueID
FROM  dbo.MeterReadingOrderERPRouteCreateResponses
WHERE (ID NOT IN (SELECT MeterReadingOrderERPRouteCreateResponseID
                  FROM  dbo.Tasks
                  WHERE (TaskType = 'MeterReading')))

any help please? I have tried this solution from: How would you do a "not in" query with LINQ? but was getting the following error: Unable to create a constant value of type 'TaskManager.Models.Task'. Only primitive types ('such as Int32, String, and Guid') are supported in this context.

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鲸落 2024-11-14 22:49:30

只是在我的脑海里做这件事，但也许这个？

var subQuery = from t in Tasks
               where t.TaskType == "MeterReading"
               select t.MeterReadingOrderERPRouteCreateResponseID

var query = from m in MeterReadingOrderERPRouteCreateResponses
            where !subQuery.Contains(m.ID)
            select new
            {
                ID = m.ID,
                UniqueID = m.UniqueID,
                RouteHeaderID = m.RouteHeaderID,
                RouteObjectState = m.RouteObjectState,
                OriginalRouteUniqueID = m.OriginalRouteUniqueID
            };

Just doing this off the top of my head, but maybe this?

var subQuery = from t in Tasks
               where t.TaskType == "MeterReading"
               select t.MeterReadingOrderERPRouteCreateResponseID

var query = from m in MeterReadingOrderERPRouteCreateResponses
            where !subQuery.Contains(m.ID)
            select new
            {
                ID = m.ID,
                UniqueID = m.UniqueID,
                RouteHeaderID = m.RouteHeaderID,
                RouteObjectState = m.RouteObjectState,
                OriginalRouteUniqueID = m.OriginalRouteUniqueID
            };

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尾戒 2024-11-14 22:49:30

var meterReadingTasks = from task in context.Tasks
                       where task.TaskType == "MeterReading"
                       select task.MeterReadingOrderERPRouteCreateResponseID;

var results = from m in context.MeterReadingOrderERPRouteCreateResponses
              where !meterReadingTasks.Contains(m.Id)
              select new { m.ID, m.UniqueID, m.RouteHeaderID, m.RouteObjectState, m.OriginalRouteUniqueID};

var meterReadingTasks = from task in context.Tasks
                       where task.TaskType == "MeterReading"
                       select task.MeterReadingOrderERPRouteCreateResponseID;

var results = from m in context.MeterReadingOrderERPRouteCreateResponses
              where !meterReadingTasks.Contains(m.Id)
              select new { m.ID, m.UniqueID, m.RouteHeaderID, m.RouteObjectState, m.OriginalRouteUniqueID};

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~没有更多了~