#Ef chain linq commands how to
obtain a list where each subject's only set property is "Name". Introduction The purpose of this article is to tell you about how to work with databases in your ASP.NET applications, such as SQL Server, SQLite, and PostgreSQL and map objects to data with the help of an open-source framework called Entity Framework Core (EF Core). Suppose you want to write a LINQ to SQL or Entity Framework query that implements. I want to avoid that circular referencing, i.e. The LINQ feature manipulates a collection of data using methods, called operators, that sort, filter, select, project, aggregate, partition, and so on. However, upon inspection, I found that the "Grades" list is also set, with a list of all the grades assigned to the subject. Var res = (s => s.Grades).ThenInclude(g => g.Subject) Īs properties are lazy-loaded, I expected each subject to only contain their "Name" property. 2 minutes to read 6 contributors Feedback In this article Writing SQL queries for entities Writing SQL queries for non-entity types Sending raw commands to the database Entity Framework allows you to query using LINQ with your entity classes. EF just keeps getting sorted down the stack and never get's popped. To do so, I use: // context being DbContext I don't doubt that there is something in the new EF that's worth learning, but my 'TODO' list on learning/improving is quite extensive: Dependency Injection, Mocking, Blazor, CSS Frameworks, CosmosDB, Azure Functions, and much much more. It uses your derived context and entity classes to reference database objects. NET language of choice) to write strongly typed queries. I want to retrieve the list of all students, with their grades, for each subject. Entity Framework Core uses Language-Integrated Query (LINQ) to query data from the database. I have 3 classes, representing a many-to-many (N-to-N) relationship between Student and Subject: Basic Dynamic LINQ VB Sample Basic Dynamic LINQ C Sample You can use either Visual Web Developer 2008.
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