When binding data to a list control, which ADO.NET class is commonly used?
- DataSet
- SqlConnection
- SqlDataAdapter
- SqlDataReader
When binding data to a list control, the SqlDataAdapter class is commonly used to fetch and manipulate data from a data source. It serves as a bridge between a data source and a DataSet, allowing you to populate the DataSet with data retrieved from the database. Once data is in the DataSet, it can be easily bound to list controls for display.
When executing a LINQ to Entities query, the ___________ method is used to retrieve the results.
- Execute
- Fetch
- Submit
- ToList
When executing a LINQ to Entities query, the ToList method is used to retrieve the results. It materializes the query and returns the results as a List collection.
ADO.NET Datasets allow you to work with data in a ___________ manner.
- Connected
- Disconnected
- Persistent
- Semi-Connected
ADO.NET Datasets allow you to work with data in a disconnected manner. This means that after retrieving data from the database, the connection to the database is closed, and the data is held in memory until it is either updated in the dataset or discarded.
Scenario: You are developing an application that needs to query a list of customer objects stored in memory. Which LINQ technology would you choose for this task?
- LINQ to Entities
- LINQ to Objects
- LINQ to SQL
- LINQ to XML
LINQ to Objects is the appropriate choice for querying in-memory collections, such as lists of customer objects. It provides powerful querying capabilities against in-memory data structures.
To prevent SQL injection attacks, it is recommended to use ________ queries.
- Dynamic
- Embedded
- Parameterized
- Prepared
Parameterized queries are a recommended practice to prevent SQL injection attacks. By using parameters, the values provided by users are treated as data rather than executable code, thereby mitigating the risk of injection attacks.
Scenario: You are building a high-performance application that requires reading a large dataset from a database. How can you efficiently achieve this using a data reader?
- Use DataSet to retrieve the entire dataset at once and then process it in memory, ensuring faster access to data without repeated database calls.
- Use Entity Framework for object-relational mapping, which abstracts the database interactions and provides a more intuitive way to work with data but may introduce overhead in high-performance scenarios.
- Use LINQ to SQL for querying the database, enabling seamless integration of database operations with C# code, but may not be as efficient for large datasets as SqlDataReader.
- Use SqlDataReader with the appropriate SQL query and optimize database interactions by fetching only the necessary columns and rows, minimizing network overhead.
By utilizing SqlDataReader along with optimized SQL queries, you can efficiently retrieve large datasets from the database while minimizing network overhead and memory consumption. Other approaches like using DataSet or Entity Framework may introduce additional overhead or may not be as efficient for high-performance scenarios compared to SqlDataReader.
Which Entity Framework feature allows you to define the structure of your database in code?
- Code-First
- Database-First
- Model-First
- Schema-First
Code-First is an Entity Framework feature that allows developers to define the structure of the database using code, typically through the use of Plain Old CLR Objects (POCO) classes. With Code-First approach, developers define their domain classes first and then generate the database schema from these classes. It offers flexibility and control over the database design and is suitable for scenarios where developers prefer to work primarily with code rather than visual designers.
LINQ to Objects is primarily used for querying data from ___________.
- Arrays
- Collections
- Databases
- XML
LINQ to Objects is used for querying in-memory data structures such as collections, arrays, or XML. It provides a convenient way to query and manipulate data.
What is the primary purpose of modifying data in datasets?
- To delete data
- To insert data
- To read data
- To update data
Modifying data in datasets primarily involves updating existing data to reflect changes made by users or applications. This can include changing values, correcting errors, or adding new information. Updating data ensures that the dataset remains accurate and up-to-date with the latest information.
The Rollback method in ADO.NET is used to ___________ a transaction.
- Abort
- Begin
- Commit
- Undo
The Rollback method in ADO.NET is used to undo or cancel a transaction, reverting any changes made since the transaction began.