logo
down
shadow

Select Top for Subquery with Entity Framework


Select Top for Subquery with Entity Framework

By : user2955857
Date : November 22 2020, 10:48 AM
fixed the issue. Will look into that further I have a Master-Detail model relationship set up in C# Entity Framework. One Master record might have multiple Detail records. I wish to bring back ALL Master records but only the first associated Detail record per Master record.
code :
Masters
   .Select(m => new{
       Master = m, 
       Detail = m.Details.OrderBy(d => d.StartDate).FirstOrDefault())
   })


Share : facebook icon twitter icon
Entity Framework - Many to Many Subquery

Entity Framework - Many to Many Subquery


By : posixpal
Date : March 29 2020, 07:55 AM
To fix this issue I asked a question about this previously but my database structure has changed, and while it made other things simpler, now this part is more complicated. Here is the previous question.
code :
var me = context
    .Users
    .First(user => user.Email = "me@example.com");

// Note that there is no call to ToList() or AsEnumerable().
var myProjects = context
    .Projects
    .Where(project => project.Users.Contains(me));

var associatedUsers = context
    .Users
    .Where(user => myProjects.Any(project => user.Project.Contains(project)));
var associatedUsers = myProjects
    .SelectMany(project => project.Users)
    .Distinct();
var myProjects = me.Projects;
Entity Framework subquery

Entity Framework subquery


By : Anndi Lomeland Jacob
Date : March 29 2020, 07:55 AM
will help you Guys I am new to Entity Framework and I'm having a bt of a problem that I have been trying to solve for quite a while. Basically I have 4 entities: users, groups, books and readingLists. A user can join a group and a group contains books - defined by readingList. I am trying to display a list of books for a specific group, the SQL looks like this: , I haven't tested it but hopefully it will work.
code :
entities.Books.Where(
b => entities.ReadingList.
Where(rl => rl.GroupId == groupId).
Select(rl => rl.BookId).
Contains(b.BookId)
)
c# Entity Framework - linq to entity query with subquery

c# Entity Framework - linq to entity query with subquery


By : Owen Wang
Date : March 29 2020, 07:55 AM
I think the issue was by ths following , If I have the following tables/entities: , I would go for something along the lines of this
code :
from i in invoices
where i.Payments.Sum(p=>p.PaymentAmount) < i.InvoiceAmount
select i;
Using subquery in entity framework

Using subquery in entity framework


By : Giuseppe Rossi
Date : March 29 2020, 07:55 AM
Does that help I am trying to write the entity framework linq query to generate the following SQL. But I am not sure how to use subqueries with entity framework. , Here is the Full query
code :
var query = (from D in
                 ((from tab1 in DbContext.Table1
                   join tab2 in DbContext.Table2 on tab1.RefId equals tab2.RefId
                   where (tab1.StatusId == 4 || tab1.StatusId == 6)
                          && (tab1.StatusDate >= startDate && tab1.StatusDate <= endDate)
                   select new
                   {
                       RefId = tab1.RefId,
                       StatusId = tab1.StatusId,
                       StatusDate = tab1.StatusDate,
                       Reference = tab2.Reference,
                       LastChangeId = (from RSC in DbContext.StateChangeTable
                                       where RSC.RefId == tab1.RefId
                                       orderby RSC.ChangeId descending
                                       select RSC.ChangeId).FirstOrDefault()
                   }))
             join RSC in DbContext.StateChangeTable on D.LastChangeId equals RSC.ChangeId
             select new StatusDetail
             {
                 RefId = D.RefId,
                 StatusId = D.StatusId,
                 StatusDate = D.StatusDate,
                 Reference = D.Reference,
                 Event = RSC.Event,
                 Information = RSC.Information,
                 CreatedDate = RSC.CreatedDate
             }).ToList();
How to do subquery in entity framework .net

How to do subquery in entity framework .net


By : billy1977
Date : March 29 2020, 07:55 AM
around this issue Here's an example of the query I'm trying to convert to entity framework
code :
// Without relation between Teachers and General_Program:    
var teachers = _context.Teachers.Where(t => t.Dept_Name = "English" && _context.General_Program.Any(p => p.Campus_Name = t.Campus_Name && p.Teacher_id = t.Teacher_ID));

// When Teachers are related to General_Program (only on ID):
var teachers = _context.Teachers.Where(t => t.Dept_Name = "English" && t.General_Program.Any(p => p.Campus_Name = t.Campus_Name));

// In case of Teachers are related to General_Program (key contains both ID and campus):
var teachers = _context.Teachers.Where(t => t.Dept_Name = "English" && t.General_Program.Any());
Related Posts Related Posts :
  • Can I organize Git submodules in a flat hierarchy?
  • How to make a server reply after receiving a request/data
  • Stored Procedure works in DB but not in C# code
  • MVVM WPF Programmatically add Child Elements
  • NCrunch and PostSharp Logging clash
  • Increasing memory usage in socket client
  • Multiple DropDownList but same action
  • How to get application memory usage as shown in Task Manager?
  • Exposing interfaces instead of concrete classes
  • How to get only postal_code data from google api?
  • Is there a way to get rid of the (by dot42) using community licence?
  • Why must I implement a function for an interface in vb.net which apparently doesn't need to be implemented in C#
  • How to remove HTML tags from the gridview Row
  • Get public post from Facebook's Graph Search API 2.x with Facebook SDK for .NET
  • C# DLL Export to Inno-Setup - Error E0434F4D
  • syntax error insert into database
  • By-pass else block of int.TryParse in Lambda Syntax
  • Retrieve "property getter" from the property name
  • Implementing generic class and multiple interfaces
  • data bind DropDownList with OleDbDataReader from Ms access 2013
  • extract specific data from HTML -CDATA- pattern in C#
  • how to compare password with salted hashed password
  • Excluding one item from list (by Index), and take all others
  • How do I find out which argument is invalid when receiving 'The best overloaded match for (...) has some invalid argumen
  • How do I use a linq query to update the underlying database table
  • How to change the coordinates of a text in a pdf page from lower left to upper left
  • Entity Framework Error: error loading specified metadata resource
  • Writing one character at a time in a C# Console Application?
  • Read write barcode data without using barcode scanner device
  • Asp.net Website is only accessible on our company internet connection and not from other network
  • Generic method to map objects of different types
  • Back button control in windows phone app
  • Get matching enum int values from list of strings
  • Ajax Control Toolkit AutoCompleteExtender displays html source character by character of the current page as autocomplet
  • How to select a node with namespace from XmlDocument?
  • multiple foreach loops inside while loop
  • Why does setting a MinimumSize break the table layout?
  • WatIn SelectList().SelectByValue() return error Run script failed
  • SignalR not works on Google Chrome
  • Sync sent mail with Sent folder
  • return a View and File in a single method in ASP.Net MVC
  • FastReport mvc GetParameter() returns null
  • How to check datatable select method returns datatable c#
  • How to sort an array based on the occurrences of the elements in a string in C#?
  • App crashes without throwing any exception in windows phone 8.1 xaml
  • How to get values from command argument from gridview on link button's click?
  • What's the proper way to convert a Vector3DF into byte array?
  • Is there a way to place a default image for control in edit/view mode?
  • How to set a click event for button in repeater control
  • how to make communication with two different process in same computer?
  • Which is the best crash logging tool for Windows Phone 8 Apps
  • Custom MarkerStyle in MS Chart Control
  • while opening the page getting error there is no row at position 0
  • Error message in Monogame: Unhandled Exception: System.DllNotFoundException: SDL2.dll
  • How to extract "Message" part from Google API error message
  • Receiving Gigs of data from Mobile Service on UpdateAsync method
  • Can't figure out what this is? Unrecognized escape sequence (Mono)
  • Calling stored procedure from another stored procedure with parameters
  • Bind Strings from an .resw file with ReswFileCodeGenerator in XAML
  • wpf DataGrid column index is not saved
  • shadow
    Privacy Policy - Terms - Contact Us © ourworld-yourmove.org