2013年1月4日 · join scg in db.StudentCourseGroup on s.StudentID equals scg.StudentID. join c in db.Course on scg.CourseID equals c.CourseID. join g in db.Group on scg.GroupID equals g.GroupID. where c.CourseName == "xyz" select new { s, g } into x. group x by x.s into studentGroups. select new MyStudent { StudentName = studentGroups.Key.StudentName,

2014年6月17日 · There are many different ways to go about using a DataRelation in a GridView. By far, the easiest way to handle this would be to just create a LINQ to DataSet query and bind that. You can also create a combined DataTable to bind to your GridView and fill it by looping through parent and child rows, similar to my example.

Hi, today I am going to show you how to join two tables in C#. First, we want to create an MVC application, give the application a name and then continue. Once our application is created, we now go to the model's folder and create three classes. In this application, I am using Events, Location, and EventsLocationViewModel.

2023年3月29日 · EF Core allows to map two or more entities to a single row. This is called table splitting or table sharing. To use table splitting the entity types need to be mapped to the same table, have the primary keys mapped to the same columns and at least one relationship configured between the primary key of one entity type and another in the same table.

In addition to querying a single table, you can also perform cross-table queries in LINQ to DataSet. This is done by using a join . A join is the association of objects in one data source with objects that share a common attribute in another data source, such as a product or contact ID.

2012年12月6日 · Try to using One to many relation in entity framework, this can help you how can we use table and its field in relationship, of two table.

2021年9月14日 · Dim table As DataTable = New DataTable() table.Columns.Add("Price", GetType(Integer)) table.Columns.Add("Genre", GetType(String)) ' Query for items with price greater than 9.99. Dim query = From i In items _ Where i.Price > 9.99 _ Order By i.Price _ Select New With {i.Price, i.Genre} query.CopyToDataTable(table, LoadOption.PreserveChanges)

2024年4月30日 · Learn how to join two DataTables in ASP.NET C# using LINQ for efficient data integration. Explore techniques to merge and query DataTables, leveraging LINQ's powerful capabilities for seamless data processing and integration within ASP.NET applications.

In C#, you can perform a LINQ Join with multiple data sources by using the join keyword and the equals keyword combined with the on keyword. This allows you to combine data from multiple collections or sources based on a common key or condition.

2023年4月7日 · LINQ to SQL is a powerful feature in C# that allows developers to interact with relational databases using LINQ queries. In this in-depth guide, we will explore the practical aspects of using LINQ to SQL, including setting up a database connection, querying data, and performing CRUD operations.