Linq Nested Group By

Figure 1 shown below is the basic standard deviation function. In this tip I will show you how I resolve a problem I have faced regarding joining tables where a null matched is expected when using LINQ. As a continuation to the articles on LINQ, in this post I will explain how to write queries and use the query operators to perform common operations such as sorting, dealing with nested data, and grouping. A typical SQL developer may have looked for a different approach. ) within the groups. Using GroupJoin, this LINQ (Lambda Expression) sample in C# groups collection "persons" with collection "languages" by a common key. In LINQ, SelectMany operator is used to select values from a collection of collection i. linq group by month problem; Linq - basic simple Answer; LINQ and nested gridview. The standard LINQ operators are a collection of 50 (give or take a few) methods that form the heart and soul of Language Integrated Query. Although DataTables doesn't have row grouping built-in (picking one of the many methods available would overly limit the DataTables core), it is most certainly possible to give the look and feel of row grouping. LINQ`s GroupBy is basically pure C# equivalent of SQL`s 'group by' statement. NET’s LINQ to JSON is good for traversing your JSON to get it into the. In this section, you will learn some complex LINQ queries. Data; using System. DebtCategory ) group dbtgroup by Faculty. And Gridview B are place in between Gridview A to display list data relate to Gridview A grouping. If someone tells you that LINQ doesn't support subqueries well, they're not wrong. I have been using LINQ for a while now for pretty standard queryies, usually against object collections. This post falls into the category of being posted for my own future reference - hopefully you'll find it useful too (and apologies to regular readers for the recent silence on theJoyOfCode. Such types of classes are known as nested class. this article, you will learn how to create a group and sort the records by the group using LINQ. Nested Group By. Now, I want to basically group these users and show the count of browser type they are using. Learn how to use LINQ in your applications with these code samples, covering the entire range of LINQ functionality and demonstrating LINQ with SQL, DataSets, and XML. Collapsable nested GridView with paging In this article we will explore how to do paging in nested collapsable gridview. An archive of the CodePlex open source hosting site. net - Linq Nested Grouping? Using LINQ To Return Element In Collection, Would Like To Return Nothing If Element Not Found? Special Nested Query In LINQ?. Abstract: I have been writing some LINQ tutorials, tips and How To's on my blog and most of these posts contain short snippets that can be used in your project or that demonstrate how to use LINQ effectively. NET framework and allows a developer to query data inside of in-memory objects, data inside of relational databases, and data inside of XML using a uniform API and syntax. Even complex relational models become intuitive and easy to manipulate. How would you group more than 4,000 active Stack Overflow tags into meaningful groups? This is a perfect task for unsupervised learning and k-means clustering — and now you can do all this inside BigQuery. We will use data binding and data relations in an effort to get a simple solution. LINQ allows queries to be executed that include grouping. The following functions might have issues if using nested groups and y ou might follow the suggestions to set up the permissions. Tag: Grouping Operators in Linq. This overload of ToDictionary takes any object that implements the IEnumerable> interface, which is a common return type when invoking LINQ operations on dictionaries, and returns a Dictionary object using the same keys and values as the dictionary in the argument list. I wanted to share them with my readers over here. Here, you will learn how to write LINQ-to-Entities queries and get the result in Entity Framework 6. To drill down LINQ versus SQL join Continue reading “Enumerable. The beauty of these operators is how they can execute against diverse data sources. GroupBy: 1. Net) that extends these languages with query operators and some other features that make it possible to integrate queries in the languages. Resources sync performance issues in Project server 2010 ; When a security group is added to a SharePoint group for a specific site, the site will not appear in the users' My Sites. Recently i did a performance benchmark of EF Core 2 Vs Dapper. ProductName group x by x. Dim result = (From n In numbers Order By n). Sum is extension method from System. Without LINQ, I would have to iterate over the set with a series of nested and complicated for each loops. In C#, a user is allowed to define a class within another class. Here's a simple example to show you how to GroupBy Multiple Values using LINQ. public partial classLINQ: System. Joins Nested queries and grouping in LINQ is useful, but differs from the manner by which different entities are typically combined in relational databases. The new LINQ AsHierarchy() extension method can be used to convert data and bind it to WPF TreeViews. One of the extension methods in the System. LINQ 101 Samples - Lambda Style This compilation is based on the 101 LINQ Samples by Microsoft. GroupBy: 1. LINQ to JSON provides a number of methods for getting data from its objects. It was a Friday. I have created a datatable which has the following columns and rows as shown in Figure. Data; using System. public void Linq() { int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 }; var numberGroups = from n in numbers group n by n % 5 into g select new { Remainder = g. But in the mean if you can try the above approach and let me know if you face any further problems. linq group by month problem; Linq - basic simple Answer; LINQ and nested gridview. This is the latest in a series of "EF Recipes" - short articles that show through practical examples how to achieve common tasks with Entity framework and ASP. Grouping with Group By. Thus, my output should look like: Solution: We need to first group the data by UserIds, and from that result-set we need to again group by individual browser names (excluding their version numbers). NET data structure you need. Well with that, we conclude this long article of some 'How Do I' operations while using LINQ to XML. "Group By" clause is used for getting aggregate value (example: count of, sum of) in one or more columns with reference to a distinct column in a table. When doing a group by in LINQ, nested collections are produced which SQL can't handle. Since i have a nested join and i am grouping at both levels it is proving to be a bit awkward. But they're also not entirely correct, either. So far, the HQL route has worked out ok - I've got quite a number of queries working just fine. 12/01/2016; 8 minutes to read +3; In this article. The SQL GROUP BY Statement. Sorting 146 Nested queries 147 Grouping 150 Using joins 151 Partitioning 155 4. Join a community of over 2. Here we will learn linq syntax with examples, linq query syntax with example, linq method syntax with examples. Querying with LINQ to SQL. NET Core sample. I use below code, Dim dt = New DataTable(tblEntTable) dt. Entity SQL provides a GROUP BY operator and a GroupBy query builder method. Because the LINQ to XML API gives us full access to LINQ's standard query operators, searching or filtering an XML document is very straightforward. A typical SQL developer may have looked for a different approach. A subquery is used to return data that will be used in the main query as a condition to further restrict the data to be retrieved. The above Linq query therefore results in two SQL queries being executed: one for the customer data and one for the order data. nested collection. NET Framework 3. There are Different Types of SQL Joins which are used to query data from more than one tables. LINQ`s GroupBy is basically pure C# equivalent of SQL`s 'group by' statement. SelectMany: Probably The Most Powerful LINQ Operator by Bart De Smet · Aug. If we group by using the SQL clause we get the flat record set. Linq to LLBLGen Pro fetches nested queries with 1 SQL query per nested query found and merges the parent and child queries together using an efficient mechanism, similar to the one used with prefetch paths. Not a compound key but a key inside a key. Like it or not, LINQ is here to stay. LINQ vs 3-tier vs binding; A Possible Scenario for LINQ; A2K: Report formatting issue grouping on "Fld<>'Value'". How to use LINQ GroupBy. Darius menyenaraikan 5 pekerjaan pada profil mereka. This is the good message : Linq is not just a way to write SQL queries in C# code, Linq is a beautiful technology every developer can use in a lot of situations. Net with Group By so that I could use a much easier to understand and maintain nested loop. PredicateBuilder is also shipped as part of LINQKit, a productivity kit for LINQ to SQL and Entity Framework. The SQL GROUP BY clause can be used in a SELECT statement to collect data across multiple records and group the results by one or more columns. So, lets move on with some example of sql like syntax for join operations with linq to sql query. Doing everything in memory is one way to do it, but it's still worse than O(n) because of the nature how the linq query has to be constructed: the nested grouping for the city is in the projection. 0) LINQ allows you to write structured type-safe queries over local object collections and remote data sources. nested collection. GroupBy ( Nested ): use group by to partition a list of each customer’s orders, first by year, and then by month. Suppose now that instead of using a local anonymous type you may want to put the result of your LINQ query in an object defined by yourself. PL/SQL Nested Table Using Initialized Values. Generic; using System. Furthermore, in Visual Basic you specify the name of the Key property directly in the grouping syntax - Group product By key = product. Join a community of over 2. LINQ to SQL allow user to query data from the database without writing sql queries by writing LINQ queries. Advertiser Disclosure: Some of the products that appear on this site are from companies from which QuinStreet receives compensation. The term ‘Lambda expression’ has derived its name from ‘lambda’ calculus which in turn is a mathematical notation applied for defining functions. There are many different ways to accomplish this task. Tag: Grouping Operators in Linq. Instead of just bombing, the LINQ to SQL engine comes up with a solution that a user may not have written themselves. I am trying to use LINQ to organize all the Pipes in the model by System, Segment, then by Size and then sum the pipe length. Using Group/By/Into will also give you the best possible performance for those complex queries. LINQ - group clause Group clause gives results by keys Can access all items with keys Group is used in place of select Requires two loops to get the result Outer loops obtains each group Inner. In fact there are several options for doing this, including the use of expression trees. Resharper's "Convert to LINQ Metohds chain" function was used to help with this conversion. 5's core features for both C# 3. Reflection Imports System. To break it down real simple: One is a look up (ToLookup) One is a dictionary (ToDictionary) Duh. Reflection Imports System. If I have a set of the data of employee which has employee ID and if a group by the sql group by departmentid, anything else that is specific to the employee has to be aggregated somehow by using Sum, Min or Max , or may be aggregate. Coz, while doing a group you are picking only the first date and you are losing the data, filter is not able to find the required data. XML Linq; Logging; Reactive Extensions (Rx) Using LINQ to Find Top 5 Processes. To better understand what a comparable solution could be, let's have a look at the main problem that LINQ solves: Query languages are often. In this article, I will demonstrate the group join because that's how you get to a left join. The GROUP BY statement groups rows that have the same values into summary rows, like "find the number of customers in each country". 8 Retrieving Data from Multiple Tables with LINQ. GroupBy: 1. Reduce or improve Linq query with nested from-where clauses. In this video, we will discuss Grouping by multiple keys. LINQ brings general-purpose query facilities to the. Now I`m back hoping to deliver you interesting stuff about advanced methods in LINQ. You can apply this concept to other list-bound controls. Since the first beta versions of LINQ we could hear comments that it is perfect for queries known at compile-time, however it is not possible to use it for building queries dynamically at runtime. The DbSet class is derived from IQuerayable. Tutorial on SSRS report grouping, expand collapse, toggle visibility, nested groups Posted on April 19, 2014 by Binary World Incase someone wants to learn how to create SSRS Groups which can expand collapse like below then check this video I embedded in this post. One of the extension methods in the System. It is easy for machines to parse and generate. Here is the example. Customizing the group header. Out of a list of persons we want to find a specific one by name. Erik Meijer editor's note: This article uses many mathematical symbols that may not render propery in your browser. The following examples show how to group data in various ways: By a single property. NET objects and a mapping from a subset of LINQ queries to DocumentDB queries. Nested select Linq. In this example, I am grouping by Age and Sex to find the count of people who have the same age and sex. Learn how to use LINQ in your applications with these code samples, covering the entire range of LINQ functionality and demonstrating LINQ with SQL, DataSets, and XML. By a computed numeric range. To break it down real simple: One is a look up (ToLookup) One is a dictionary (ToDictionary) Duh. Even complex relational models become intuitive and easy to manipulate. JavaScript is amazing, we all know that already. 12/01/2016; 8 minutes to read +3; In this article. Linq Imports System. I wanted to share them with my readers over here. What's the problem with LINQ? As outlined by Joe Duffy, LINQ introduces inefficiencies in the form of hidden allocations, from The 'premature optimization is evil' myth: To take an example of a technology that I am quite supportive of, but that makes writing inefficient code very easy, let's look at LINQ-to-Objects. In this example grouping occurred by first column (first column was considered as a key in grouping). If I have a set of the data of employee which has employee ID and if a group by the sql group by departmentid, anything else that is specific to the employee has to be aggregated somehow by using Sum, Min or Max , or may be aggregate. This integration of querying capabilities allows compile time checking of query expressions as well as intellisence support from IDE's using the reflection. The results of the grouping can use automatic naming, and in other cases can be explicitly named. When you iterate over a query that produces a sequence of groups, you must use a nested foreach loop. It was a Friday. When doing a group by in LINQ, nested collections are produced which SQL can’t handle. I want to perform Group By based on Place column in MyTable and I need to get the Name column values for the grouped value which should look as shown in Figure. SQL MAX() function with GROUP by, ORDER by: How the GROUP BY and ORDER BY clause along with the SQL MAX() can be used to find the maximum value of a column over each group. In this article I show that this can be actually done very well for most of the common cases. Previous versions of Entity Framework Core doesn't support database level grouping and LINQ GroupBy is translated locally. Any ideas?. I have datatable with two column, line and duration. The ValueHolder factor is the same variable created from the from operator. The new LINQ AsHierarchy() extension method can be used to convert data and bind it to WPF TreeViews. 'GROUPING BY' IN LINQ TO OBJECTS. In this example we will show you, How to. Assuming you had two properties, and wanted to group by both State and Country:. How to: Use the Group Clause in LINQ Posted Wednesday, March 26, 2008 9:29 AM by CoreyRoth As you know, LINQ is similar in a lot of ways to T-SQL, but as you go to start doing things with grouping or joining, you will find that that there are some syntactical differences. This interface is implemented with the MenuItemsGroup. Like it or not, LINQ is here to stay. Grouping Results in LINQ. 'The Linq query. As I spend more time reviewing code with clients and on public forums, I’m constantly seeing cases where people have issues with Outer joins in LINQ and the various flavors of LINQ. NET languages (C# and VB. Not a compound key but a key inside a key. It is easy for humans to read and write. Addresses is a List'(T). GroupBy ( Nested ): use group by to partition a list of each customer’s orders, first by year, and then by month. Paginating blog posts from SQL server using nested LINQ statements. Because the LINQ to XML API gives us full access to LINQ's standard query operators, searching or filtering an XML document is very straightforward. Just saw this being discussed internally and thought that it was quite useful to a lot of you out there so I thought I'd share. Here's a simple example to show you how to GroupBy Multiple Values using LINQ. I have the following query working in my code and now want to move into a separate class as a method that I call with List, but having trouble determining what TYPE I need to. I need to find out how many of each instance of "colour" are in the datatable. This sample shows different uses of Grouping Operators LINQ - Grouping Operators in C# for Visual Studio 2010 This site uses cookies for analytics, personalized content and ads. Unfortunately though it doesn't work in. Before we start, displayed below is the sample data used in the queries below: Simple Group by Anonymous Type - Grouping by Month and Year in a Date. Those objects also. Most of the collections in. It can be done by Select method or using selector as a parameter of the Average method. GROUP BY returns one records for each group. LINQ is an acronym of "Language Integrated Query" and its main feature is to allows users to write SQL style of queries with in code using query syntax's. after changing it to below red mark it works fine. We have seen the Join operator in the previous section. What's the problem with LINQ? As outlined by Joe Duffy, LINQ introduces inefficiencies in the form of hidden allocations, from The 'premature optimization is evil' myth: To take an example of a technology that I am quite supportive of, but that makes writing inefficient code very easy, let's look at LINQ-to-Objects. If you’re families with Different Types of SQL Joins which are used to query data from more than one tables, LINQ has a JOIN query operator that provide SQL JOIN like behavior (and syntax … depending on which LINQ syntax you prefer Query or Fluent syntax). There are Different Types of SQL Joins which are used to query data from more than one tables. And Gridview B are place in between Gridview A to display list data relate to Gridview A grouping. I remember sitting on the edge of my seat watching the 2005 PDC (Professional Developers Conference) videos that first showed LINQ (Language Integrated Query). Calling functions in LINQ queries. First and when to use. Handling data structures, we sometimes have to extract and flatten nested collections into a single one. The GROUP BY statement groups rows that have the same values into summary rows, like "find the number of customers in each country". If the category id is the same but the year released is different, then a row is treated as a unique one. 2 Design patterns 180. Grouping numbers based on occurrences? LINQ grouping in object; Grouping troubles in LINQ; nested Grouping in Linq; Dynamic grouping on element and attributes names; Apply rule based grouping on Java enum; Efficient grouping in pandas based on another Series; Xquery grouping results based on condition; Grouping Objects In Array Based On. I have optimization problem with list of objects. The need to combine results in multiple SQL Server tables for producing a list of records or summary reports are often a challenge to us as a developer. Category Into Group. In this article I show that this can be actually done very well for most of the common cases. To do this I defined a new type (the MyClass type) with 2 properties (ID and Name) inside the LINQ to SQL Designer as shown in the following figures and I rebuilt the whole project. SelectMany Method (IEnumerable, Func>) Projects each element of a sequence to an IEnumerable and flattens the resulting sequences into one sequence. Sample LINQ Queries. Resources sync performance issues in Project server 2010 ; When a security group is added to a SharePoint group for a specific site, the site will not appear in the users' My Sites. Group By - Where Linq Query. NET, Entity Framework, LINQ to SQL, NHibernate / Linq query using group by in vb. So now lets have a look at the ObservableGroupCollection:. com - I've been away on holiday). Not only can you use the operators locally to query object in memory, but you. Below is a sample source code demonstrating on how to remove duplicates and get distinct records in List using LINQ and C#? How to Remove Duplicates and Get Distinct records from List using LINQ? using System; using System. Now, you can also perform nested queries with LINQ. ProductName group x by x. Linq Public Class MainClass Public Shared Sub Main Dim numbers() As Integer = {5, 4, 1, 3, 10} Dim numberGroups = From num In numbers _ Group num By Remainder = num Mod 2 Into NumberGroup = Group _ Select Remainder, NumberGroup For Each g In numberGroups For Each n In g. To better understand what a comparable solution could be, let's have a look at the main problem that LINQ solves: Query languages are often. 1st SPROC are to get the grouping data for Gridview A. By Boolean predicate or other expression. LINQ to JSON provides a number of methods for getting data from its objects. Linq Imports System. You also will see some code for LINQ to SQL that is pretty straightforward and my last article, "Search and Replace with Regular Expressions," and my upcoming book, LINQ Unleashed: for C#, cover LINQ to SQL in detail. I have been using LINQ for a while now for pretty standard queryies, usually against object collections. GroupBy ( Nested ): use group by to partition a list of each customer's orders, first by year, and then by month. This particular example looks at grouping data by year and month in MVC 5 with Entity Framework 6. By a computed numeric range. Index in Nested ListOct 27, 2014. With LINQ, we can use SelectMany() to do just that. group by author 52 var titlesByAuthor = 53 from The LINQ query does this by using a nested query in the. Linq namespace contains the classes for LINQ to XML. Linq query for nested list in C#. Now we select our subsets into the Group object, which will consist of a key and a collection of each book which matches this key. View Marcos Vinícius Lourenço de Deus’ profile on LinkedIn, the world's largest professional community. Many people are looking for a comparable solution in the Java world. For example, SQL database has no built-in Zip operation support. 5 provides querying capabilities to Object Oriented programming languages like C# or VB. The GROUP BY clause will gather all of the rows together that contain data in the specified column(s) and will allow aggregate functions to be performed on the one or more columns. Use the ToArray method to create an array from results of a LINQ query. To keep it simple we just look for the first person with the name. With this method from the System. NET AJAX Grid. It was a Friday. Multiple “order by” in LINQ ; How do I get a consistent byte representation of strings in C# without manually specifying an encoding? When to use. Coz, while doing a group you are picking only the first date and you are losing the data, filter is not able to find the required data. How would you group more than 4,000 active Stack Overflow tags into meaningful groups? This is a perfect task for unsupervised learning and k-means clustering — and now you can do all this inside BigQuery. I was looking for a solution to flatten and unflatten nested lists of numpy arrays, but only found this unanswered question, so I came up with this:. Here's an explanation of how the default example for LINQ nested grouping actually works. Complex queries can be solved with a combination of simpler LINQ queries, anonymous objects and the Group/By/Into clauses. We will use the Northwind sample for our example. I have the following query working in my code and now want to move into a separate class as a method that I call with List, but having trouble determining what TYPE I need to. tldr; safely access nested objects in JavaScript in a super cool way. I am also. The beauty of these operators is how they can execute against diverse data sources. SelectMany: Probably The Most Powerful LINQ Operator by Bart De Smet · Aug. Grouping with Group By. Group By - Where Linq Query. Each group has a key. Reflection Imports System. Nested Group By. 1 Common scenarios 161 Querying nongeneric collections 162 Grouping by multiple criteria 164 Dynamic queries 167 LINQ to Text Files 178 5. nested collection. The LINQ project (see []) is an extension to. Key select StudentGroup. If we are only interested in the aggregated results of each group, we can optimize GroupBy with the following implementation: We use a dictionary to hold the accumulated value for each group. So we can created the data structure with nested data. Here's a simple example to show you how to GroupBy Multiple Values using LINQ. Nested Queries. But a few things in JavaScript are really weird and they make us scratch our heads a lot. NET Framework 3. The beauty of these operators is how they can execute against diverse data sources. I was looking for a solution to flatten and unflatten nested lists of numpy arrays, but only found this unanswered question, so I came up with this:. To do this I defined a new type (the MyClass type) with 2 properties (ID and Name) inside the LINQ to SQL Designer as shown in the following figures and I rebuilt the whole project. C# - LINQ - Flatten nested Lists Enumerable. Reflection Imports System. The usual example for nested grouping looks like this: from student in Students group student by student. Put an end to those hundreds of Visual Studio Console projects cluttering your source folder and join the revolution of LINQPad scripters and incremental developers. A group clause projects the result of an expression into a set of groups, based on a grouping condition, where each group. LINQ`s GroupBy is basically pure C# equivalent of SQL`s 'group by' statement. In this video, we will discuss Grouping by multiple keys. As a continuation to the articles on LINQ, in this post I will explain how to write queries and use the query operators to perform common operations such as sorting, dealing with nested data, and grouping. JSON (JavaScript Object Notation) is a lightweight data-interchange format. This article explains how to convert data from a self referencing table (adjacency model) to a hierarchy of nested collections (nested set model). The following example shows how to create nested groups in a LINQ query expression. In this article we will show you, How to Select First Row in each SQL Group By group with example. This is an uninteresting sentence that acts as a placeholder. We will use data binding and data relations in an effort to get a simple solution. Linq namespace, you can apply grouping to many collections. Lookups A lookup is a key […]. LINQ 101 Samples - Lambda Style This compilation is based on the 101 LINQ Samples by Microsoft. GROUP BY returns one records for each group. Such types of classes are known as nested class. Sum (LINQ) Enumerable. Page {protected void Page_Load(objectsender, EventArgs e) {List empList = newList();. But I wanted to remove the nested foreach loops and do it in one simple LINQ query. Grouping in LINQ is weird (IGrouping is your friend) - Mike Taulty's Blog - Mike Taulty's Blog. 5 is out with all its LINQ query operator goodness, I feel like going on a mean streak of trashing a lot of o. Visual studio doesn't support the default_if_empty, group_by, group_join, join, order_by, select_many, and then_by extensions, and it doesn't support orderby, group, and nested from clauses. Linq Public Class MainClass Public Shared Sub Main Dim numbers() As Integer = {5, 4, 1, 3, 10} Dim numberGroups = From num In numbers _ Group num By Remainder = num Mod 2 Into NumberGroup = Group _ Select Remainder, NumberGroup For Each g In numberGroups For Each n In g. The System. Entity SQL provides a GROUP BY operator and a GroupBy query builder method. In this article, I will demonstrate the group join because that's how you get to a left join. Listing 3-29. Resharper's "Convert to LINQ Metohds chain" function was used to help with this conversion. NET data structure you need. I've tested it for in memory collections, whether or not your particular DB provider will handle it well might vary, or whether it performs well is unknown. Here is the complete code snippet:. By using LINQ to order and group the people by their last name we have a fast and save way to do this. By Peter Vogel; 02/20/2017. [Entity Framework] Using Include with lambda expressions October 3, 2010 Thomas Levesque 15 Comments I’m currently working on a project that uses Entity Framework 4. Instead of just bombing, the LINQ to SQL engine comes up with a solution that a user may not have written themselves. LINQ Group query - simplifying. ProductName into g orderby g. This particular example looks at grouping data by year and month in MVC 5 with Entity Framework 6. Many people are looking for a comparable solution in the Java world. The following functions might have issues if using nested groups and y ou might follow the suggestions to set up the permissions. Create a nested group. To construct a function to perform standard deviation over a set of numbers, you need to examine the math. Linq sorting on sort order of inner group [closed] Ask Question Asked 5 years, 5 months ago. The true boolean to grp. select messageid, comment from Message where isactive = 1 and messageid in ( select messageid from org. NET programming model which expresses computation as queries on streams of objects. Here's a simple example to show you how to GroupBy Multiple Values using LINQ. On the File menu, point to New, and then click Project. ProductName into g orderby g. I'd like to make a lot of fuss over how you obtain data with LINQ to SQL, but it is pretty easy. This interface is implemented with the MenuItemsGroup. public void Linq() { int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 }; var numberGroups = from n in numbers group n by n % 5 into g select new { Remainder = g. It does this operation by itself thereby reducing the lines of code that a normal program would typically have. Now, you can also perform nested queries with LINQ. OrgUser where OrgId in ( select ChildOrgId from OrgRelation where ParentOrgId = 10001 ) ) group by. LINQ queries can only be used with data sources which implements the IEnumerable interface. Linq Imports System. 5's core features for both C# 3. I use below code, Dim dt = New DataTable(tblEntTable) dt. Linq namespace, you can apply grouping to many collections. Generic; using System.