how can I code a recursive query in an Entity Framework model?

Posted by Greg on Stack Overflow See other posts from Stack Overflow or by Greg
Published on 2010-05-30T12:02:48Z Indexed on 2010/05/30 12:22 UTC
Read the original article Hit count: 1299

Filed under:

entity-framework

|

recursion

|

linq-to-entities

Hi,

I have a model which includes NODES, and RELATIONSHIPS (that tie the nodes together, via a parent_node, child_node arrangement).

Q1 - Is there any way in EF / Linq-to-entities to perform a query on nodes (e.g. context.Nodes..) to find say "all parents" or "or children" in the graph?

Q2 - If there's not in Linq-to-entities, is there any other way to do this other than writing a method that manually goes through and doing it?

Q3 - If manual is the only way to do it, should I be concerned about the number of database hits that will be going out to the database as the method keeps recursing through the data? Or more specifically, is there any EF caching type feature that might assist here in ensuring the method is performance from a "number of database hits" point of view?

thanks

thanks

© Stack Overflow or respective owner

Related posts about entity-framework

Differences Between NHibernate and Entity Framework

as seen on ASP.net Weblogs - Search for 'ASP.net Weblogs'
Introduction NHibernate and Entity Framework are two of the most popular O/RM frameworks on the .NET world. Although they share some functionality, there are some aspects on which they are quite different. This post will describe this differences and will hopefully help you get started with the one… >>> More
Entity Framework & Binding syncronisation

as seen on Stack Overflow - Search for 'Stack Overflow'
* EDIT * Sorry, I should make it clearer. Imagine I have an entity: public class MyObject { public string Name { get; set; } } And I have a ListBox: <ListBox x:Name="lbParts"> <ListBox.ItemTemplate> <DataTemplate> <TextBlock Text="{Binding Name}"/> … >>> More
Joins and UI Binding with the Entity Framework

as seen on Internet.com - Search for 'Internet.com'
Learn how to build queries with the Entity Framework that involve multiple tables as well as binding in the UI with the EntityDataSource. >>> More
Frederick .NET User Group April 2010 Meeting

as seen on Geeks with Blogs - Search for 'Geeks with Blogs'
FredNUG is pleased to announce that we have an excellent speaker lined up for April. On April 20th, we’ll start with pizza and social networking at 6:30 PM. Then, starting at 7 PM, Dane Morgridge will present “Getting Started with Entity Framework 4” The scheduled agenda is: 6:30 PM - 7:00… >>> More
[News] NHibernate vs MS Entity Framework

as seen on Dot Net Guru - Search for 'Dot Net Guru'
Voil? une question qui se posera de plus en plus avec la sortie prochaine de .NET V4 et Entity Framework V4, l'outil de mapping objet/relationnel de Microsoft. M?me s'il est vrai que l'opinion de Ayende peut para?tre biais?e du fait qu'il est contributeur NHibernate, son point de vue et surtout ses… >>> More

Related posts about recursion

tail recursion vs. forward recursion

as seen on Stack Overflow - Search for 'Stack Overflow'
Can someone give me the difference between these two kinds recursions and example? specifically in ocaml. Thanks >>> More
Are there advantages for using recursion over iteration - other than sometimes readability and elegance?

as seen on Programmers - Search for 'Programmers'
I am about to make two assumptions. Please correct me if they're wrong: There isn't a recursive algorithm without an iterative equivalent. Iteration is always cheaper performance-wise than recursion (at least in general purpose languages such as Java, C++, Python etc.). If it's true that recursion… >>> More
Python recursive function error: "maximum recursion depth exceeded"

as seen on Stack Overflow - Search for 'Stack Overflow'
I solved Problem 10 of Project Euler with the following code, which works through brute force: def isPrime(n): for x in range(2, int(n**0.5)+1): if n % x == 0: return False return True def primeList(n): primes = [] for i in range(2,n): if isPrime(i): … >>> More
Dynamic Programming Recursion and a sprinkle of Memoization

as seen on Stack Overflow - Search for 'Stack Overflow'
I have this massive array of ints from 0-4 in this triangle. I am trying to learn dynamic programming with Ruby and would like some assistance in calculating the number of paths in the triangle that meet three criterion: You must start at one of the zero points in the row with 70 elements. Your… >>> More
How does the recursion here work?

as seen on Stack Overflow - Search for 'Stack Overflow'
code 1: public static int fibonacci (int n){ if (n == 0 || n == 1) { return 1; } else { return fibonacci (n-1) + fibonacci (n-2); } } how can you use fibonacci if you haven't gotten done explaining what it is yet? I've been able to understand… >>> More