12 May Entity Framework Wikipedia
Here, you can observe we have created the connection object, created the data adapter object, and created Dataset, Data Tables, and DataView objects. And here we are also https://deveducation.com/ writing the SQL Commands to fetch the data from the database tables and fill the dataset. We can avoid all these ADO.NET Related things if we use Entity Framework.
In code, you might want to work with objects in an object oriented fashion. Various profilers are commercially available to troubleshoot performance issues using Entity Framework, both for EF and EF Core variants. Using -Verbose will give detailed output on what the Update-Database command is doing, which can help pinpoint issues. When working with Entity Framework Core, you may encounter various issues that can impede development.
Let’s find the highest-rated production by averaging the Star value on a Rating. We can see that the Character class has a one to one relationship to both an Actor entity and a Production entity. EF Core uses advantages of entity framework the naming convention of [Entity]Id to map values to the in-memory object instance. Developers can override EF Core conventions, but I recommend folks starting with EF Core use the default conventions.
The ChangeTrack keeps track of the states of each entity as and when an action is performed. Most of the time you don’t have to write any SQL yourself, and iterating is very easy using your language built in functions. When you make any changes to the object, the ORM will usually detect this, and mark the object as ‘modified’. When you save all the changes in your ORM to the database, the ORM will automatically generate insert/update/delete statements, based on what you did with the objects. Lazy Loading is a pattern where related data is automatically loaded from the database when the navigation property is accessed.
Features of Entity Framework
From our next article onwards, I am going to explain everything in detail. Once you click on the Next button, it will open a popup asking you to choose the Entity Framework version as shown below. From this window, select Entity Framework 6.x and click on the Next button as shown in the below image. Once you click on the Next button, It will open choose your data connection wizard as shown below. From this window click on the New Connection button as shown in the below image.
Likely the most complex query in this list, let’s find actors playing characters in different productions. We’ll need to start at the Actors entity and navigate through the Characters collection while including the Production information. An element to note in our LINQ query is the value of 1 passed to the Take method. This value exists in C# but does not exist in our SQL query unless we give it to our database engine. Aggregation is one of the most important reasons to use a relational database, and with LINQ, using an aggregate function like Sum, Average, and Max is straightforward.
Setting Up The Development Environment
Entity Framework Core maps this C# class to our People table via conventions. With our context created, we can execute database commands like queries, inserts, and deletions. In the above context class, Students, and Grades properties of type DbSet are called entity sets. EF API will create the Students and Grades tables in the database, as shown below. Before we answer these exciting questions, let’s talk about LINQ, also known as Language-Integrated Query syntax.