What does CRUD stand for in the context of database operations?
- Change, Read, Update, Delete
- Connect, Retrieve, Update, Disconnect
- Copy, Remove, Update, Delete
- Create, Retrieve, Update, Delete
CRUD stands for Create, Retrieve, Update, Delete. It represents the four basic operations that can be performed on data: Create (insert), Retrieve (select), Update (modify), and Delete (remove). These operations are fundamental in database management systems and are used extensively in applications dealing with persistent data storage. Understanding CRUD operations is crucial for developers working with databases.
In ADO.NET, what is an optimistic concurrency model?
- Lock-based concurrency model
- Pessimistic concurrency model
- Row versioning concurrency model
- Timestamp-based concurrency model
In an optimistic concurrency model, multiple users are allowed to access and modify data simultaneously without locking the data. Instead, when updating data, ADO.NET compares the original data with the current data to ensure that no changes have occurred since the data was initially retrieved.
You want to call a stored procedure in ADO.NET that updates multiple records in a database. What is the recommended approach for handling the output and any potential errors?
- Use SqlCommand.ExecuteNonQuery method to execute the stored procedure. Check for any errors using try-catch block and handle the output as needed.
- Use SqlCommand.ExecuteReader method to execute the stored procedure and handle any output or errors using SqlDataReader.
- Use SqlConnection to execute the stored procedure and handle output using SqlDataReader.
- Use SqlDataAdapter to execute the stored procedure and handle output using DataSet.
SqlCommand.ExecuteNonQuery method is the recommended approach. It executes the SQL statement against the connection and returns the number of rows affected. Errors can be caught using a try-catch block. SqlDataReader is used for reading a forward-only stream of rows.
In LINQ to SQL, DataContext manages the ___________ between your application and the database.
- Communication
- Connection
- Interaction
- Transaction
DataContext manages the connection between your application and the database in LINQ to SQL. It tracks changes made to the objects and submits them to the database. This ensures efficient communication and interaction with the database.
In LINQ to SQL, the DataContext class represents the ___________.
- Connection to the Database
- Object Model
- Query
- Table in the Database
The DataContext class in LINQ to SQL represents the connection to the database. It manages database connections and transactions and provides methods for querying and submitting changes to the database.
The DataAdapter's Update method is used to ___________ changes made to a dataset back to the database.
- Reflect
- Submit
- Propagate
- Transfer
The correct option is "Propagate". The Update method of DataAdapter propagates changes from the DataSet to the corresponding data source in the database.
In LINQ to Entities, what is the primary purpose of the DbContext class?
- Handles database connection and authentication
- Provides metadata about the database schema
- Represents a collection of database entities
- Represents a session with the database and provides CRUD operations on entities
In LINQ to Entities, the DbContext class serves as a bridge between the domain classes (entities) in the application and the database. It represents a session with the database and provides CRUD (Create, Read, Update, Delete) operations on entities, allowing developers to interact with the database using object-oriented principles.
In Entity Framework, what is the role of the DbContext class?
- Acts as a bridge between the domain/entity classes and the database
- Manages database connections and transactions
- Performs database migrations and updates
- Represents the conceptual model of the data
The DbContext class in Entity Framework acts as a bridge between the domain or entity classes and the database. It provides functionalities for querying, saving, updating, and deleting data from the database using LINQ to Entities. It also manages the database connection and transactions.
You need to execute a stored procedure in ADO.NET that inserts data into a database table. Which ADO.NET object would you use for this task, and how would you pass the necessary parameters?
- SqlCommand
- SqlDataAdapter
- SqlConnection
- SqlDataReader
SqlCommand is the correct option. It represents a Transact-SQL statement or stored procedure to execute against a SQL Server database. Parameters can be passed using the SqlCommand.Parameters collection. SqlDataReader is used for reading a forward-only stream of rows. SqlConnection represents a connection to a SQL Server database. SqlDataAdapter is used to fill a DataSet and update a SQL Server database.
Scenario: Your application needs to display user-generated content in a customizable format. You want to maximize performance while maintaining flexibility in layout design. Which ADO.NET control should you use, and how can you optimize it for performance?
- DataList
- GridView
- ListView
- Repeater
The ListView control in ADO.NET is the recommended choice for displaying user-generated content in a customizable format while maximizing performance. ListView offers flexibility in layout design through customizable templates, allowing you to define the presentation of data according to your requirements. Additionally, ListView provides built-in support for features like sorting, paging, and editing, offering a comprehensive solution for managing user-generated content. To optimize ListView for performance, consider implementing efficient data binding techniques, such as using data caching and optimizing database queries to minimize data retrieval overhead. Furthermore, optimizing the rendering process by reducing unnecessary markup and implementing client-side caching can help improve page load times and overall performance.