使用LINQPad调试Linq和Entity Framework

         LinqPad 可以Load一个包含有EF Model的程序集。这样极大的方便调试LINQ.而不需要VisualStudio， 让我们来演示一下。首选创建一个Connection，看下图：

通过点击Browse加载一个程序集，然后你可以看左右的目录树结构：

 

输入这样的LINQ Expression:

                from forumGroupMapping in ForumGroupMappings
                 join forumGroup in ForumGroups
                 on forumGroupMapping.ForumGroupId equals forumGroup.Id

                 join teamForumGroupMapping in TeamForumGroupMappingAccesses
                 on forumGroupMapping.Id equals teamForumGroupMapping.ForumGroupMappingId

                 join teamRole in TeamRoleAgentMappings
                 on teamForumGroupMapping.TeamId equals teamRole.TeamId

                 join team in Teams
                 on teamRole.TeamId equals team.Id

                 where team.IsActive.Equals(true) &&
                 team.IsDeleted.Equals(false) &&
                 teamRole.IsActive.Equals(true) &&
                 teamRole.IsDeleted.Equals(false) &&
                 teamForumGroupMapping.IsActive.Equals(true) &&
                 teamForumGroupMapping.IsDeleted.Equals(false) &&
                 forumGroupMapping.IsActive.Equals(true) &&
                 forumGroupMapping.IsDeleted.Equals(false) &&
                 forumGroup.IsActive.Equals(true) &&
                 forumGroup.IsActive.Equals(true) &&
                 teamRole.AgentId.Equals(new Guid("476c261f-b25a-4c0b-ba06-f3c9f7b00eeb"))
                select forumGroupMapping

 

执行后可以看到这个T-SQL：

   1:  SELECT 

   2:  [Filter2].[Id1] AS [Id], 

   3:  [Filter2].[ForumGroupId] AS [ForumGroupId], 

   4:  [Filter2].[ForumId] AS [ForumId], 

   5:  [Filter2].[RootForumId] AS [RootForumId], 

   6:  [Filter2].[RootForumExternalId] AS [RootForumExternalId], 

   7:  [Filter2].[PlatformTypeId] AS [PlatformTypeId], 

   8:  [Filter2].[Locale] AS [Locale], 

   9:  [Filter2].[CreatedBy1] AS [CreatedBy], 

  10:  [Filter2].[CreatedDate1] AS [CreatedDate], 

  11:  [Filter2].[LastUpdatedBy1] AS [LastUpdatedBy], 

  12:  [Filter2].[LastUpdatedDate1] AS [LastUpdatedDate], 

  13:  [Filter2].[IsActive1] AS [IsActive], 

  14:  [Filter2].[IsDeleted1] AS [IsDeleted]

  15:  FROM   (SELECT [Filter1].[Id1], [Filter1].[ForumGroupId], [Filter1].[ForumId], [Filter1].[RootForumId], [Filter1].[RootForumExternalId], [Filter1].[PlatformTypeId], [Filter1].[Locale], [Filter1].[CreatedBy1], [Filter1].[CreatedDate1], [Filter1].[LastUpdatedBy1], [Filter1].[LastUpdatedDate1], [Filter1].[IsActive1], [Filter1].[IsDeleted1], [Filter1].[TeamId1], [Extent4].[TeamId] AS [TeamId2]

  16:      FROM   (SELECT [Extent1].[Id] AS [Id1], [Extent1].[ForumGroupId] AS [ForumGroupId], [Extent1].[ForumId] AS [ForumId], [Extent1].[RootForumId] AS [RootForumId], [Extent1].[RootForumExternalId] AS [RootForumExternalId], [Extent1].[PlatformTypeId] AS [PlatformTypeId], [Extent1].[Locale] AS [Locale], [Extent1].[CreatedBy] AS [CreatedBy1], [Extent1].[CreatedDate] AS [CreatedDate1], [Extent1].[LastUpdatedBy] AS [LastUpdatedBy1], [Extent1].[LastUpdatedDate] AS [LastUpdatedDate1], [Extent1].[IsActive] AS [IsActive1], [Extent1].[IsDeleted] AS [IsDeleted1], [Extent3].[TeamId] AS [TeamId1]

  17:          FROM   [dbo].[ForumGroupMapping] AS [Extent1]

  18:          INNER JOIN [dbo].[ForumGroup] AS [Extent2] ON [Extent1].[ForumGroupId] = [Extent2].[Id]

  19:          INNER JOIN [dbo].[TeamForumGroupMappingAccess] AS [Extent3] ON [Extent1].[Id] = [Extent3].[ForumGroupMappingId]

  20:          WHERE (1 = [Extent1].[IsActive]) AND (0 = [Extent1].[IsDeleted]) AND (1 = [Extent2].[IsActive]) AND (1 = [Extent2].[IsActive]) AND (1 = [Extent3].[IsActive]) AND (0 = [Extent3].[IsDeleted]) ) AS [Filter1]

  21:      INNER JOIN [dbo].[TeamRoleAgentMapping] AS [Extent4] ON [Filter1].[TeamId1] = [Extent4].[TeamId]

  22:      WHERE (1 = [Extent4].[IsActive]) AND (0 = [Extent4].[IsDeleted]) AND (cast('476c261f-b25a-4c0b-ba06-f3c9f7b00eeb' as uniqueidentifier) = [Extent4].[AgentId]) ) AS [Filter2]

  23:  INNER JOIN [dbo].[Team] AS [Extent5] ON [Filter2].[TeamId2] = [Extent5].[Id]

  24:  WHERE (1 = [Extent5].[IsActive]) AND (0 = [Extent5].[IsDeleted])

同时你可以查看这个查询生成IL。这里就不截图了。

LINQPad 支持 C# 4.0 和 Framework 4.0 :

• LINQ to Objects
• LINQ to SQL and Entity Framework
• LINQ to XML
• Parallel LINQ

您还能查询:

• OData / WCF Data Services - including StackOverflow, and Windows DataMarket
• SQL Azure, Oracle, SQLite and MySQL
• Microsoft StreamInsight
• Microsoft Dynamics CRM
• Mindscape LightSpeed ORM
• (Even old-fashioned SQL!)
   

希望这篇POST对您开发有帮助。

作者：Petter Liu
出处：http://www.cnblogs.com/wintersun/
本文版权归作者和博客园共有，欢迎转载，但未经作者同意必须保留此段声明，且在文章页面明显位置给出原文连接，否则保留追究法律责任的权利。
该文章也同时发布在我的独立博客中-Petter Liu Blog。