It therefore increases database lock contention and the probability of database deadlocks occurring. It’s also very easy for a developer to inadvertently execute a long-running computation or a remote service call without realizing or even knowing that they’re within the context of an open database transaction. To delete an entity using Entity Framework, you use the Remove method on DbSet. The entity is removed from the change tracker and is no longer tracked by the DbContext.
- The DbSet properties like CompanyTable and Orders will perform the entire operations.
- The Correct way to use DbContext in our application is by creating a class and deriving from the DbContext.
- In practice, as you use a DbContext instance to load, update, add and delete persistent entities, the instance keeps track of those changes in memory.
- It allows you to query, insert, update and delete operations on the entities.
Then you’re forced to use multiple DbContexts, each one dedicated to a specific SQL database. With an injected DbContext, you’re simply better off limiting yourself to single-threaded code or at least to a single logical flow of execution. Which is perfectly fine for many applications but it will become a major limitation in certain cases.
What is Code First approach in Entity Framework and how does it work?
It’s not merely about understanding how to utilize DbContext or how it functions. As we transition into our next set of questions, you’ll discover how EF can be used to define the structure of your database using codes, highlighting the ingenious ‘Code First’ approach. To use DbContext, we first need to create a subclass of it and expose DbSet properties to represent tables in the database.
It stores the entities which have been retrieved during the lifetime of a context class. As you can see in the above example, the context class (SchoolDBEntities) includes the entity set of type DbSet for all the entities. It also includes functions for the stored procedures and views included in EDM.
There’s no built-in way to override the default isolation level used for AutoCommit and automatic explicit transactions
I’m using a scaffold-dbcontext command that has worked in the past. When dealing with massive volumes of data, you should strive to retrieve only the required what is entity framework records for the specific query. When fetching data, you should use projections to pick just the required fields and avoid retrieving unnecessary fields.
A service method, as defined above, is responsible for defining the boundary of a business transaction. Perhaps the main source of confusion when it comes to managing DbContext instances is understanding the difference between the lifetime of a DbContext instance and the lifetime of a business transaction and how they relate. For certain types of applications however, the inherent limitations of these approaches pose problems.