Connection pooling in ADO.NET helps in ___________ database connections for better performance.
- Limiting
- Managing
- Reducing
- Sharing
Connection pooling in ADO.NET involves reducing the number of times connections need to be opened and closed by reusing existing connections, which ultimately improves performance by reducing overhead.
Scenario: You are developing an application that needs to interact with a SQL Server database. Which component of Entity Framework would you use to define the data model and work with the database?
- Code-First Approach
- DbContext
- DbSet
- Entity Data Model
DbContext serves as the primary class in Entity Framework for interacting with the database. It represents a session with the database and can be used to query and save instances of your entities. It also allows you to define the data model through entity classes and their relationships. DbSet, on the other hand, represents a collection of entities of a specific type in the context. Entity Data Model is a conceptual model that describes the structure of data, but DbContext is the component used to interact with the database. Code-First Approach is a methodology for creating the data model through code rather than using a visual designer, but DbContext is the component that enables this approach within Entity Framework.
What is the purpose of the SqlDataReader class in ADO.NET?
- Executes SQL commands and returns a result set
- Provides a way to read a forward-only stream of rows from a SQL Server database
- Represents a disconnected architecture for interacting with a database
- Retrieves data from the database and populates a DataSet
The purpose of the SqlDataReader class in ADO.NET is to provide a way to read a forward-only stream of rows from a SQL Server database. It enables efficient data retrieval and processing by sequentially reading data from the database without the need to cache the entire result set in memory.
ADO.NET provides mechanisms to automatically ___________ and ___________ connections when they are no longer needed.
- Close; Dispose
- Connect; Disconnect
- Open; Close
- Open; Dispose
In ADO.NET, the methods Open() and Dispose() are used to respectively establish and release connections. The Open() method opens a connection to a data source, while the Dispose() method releases the resources used by the connection.
Scenario: Your application requires real-time updates of data in the UI whenever changes occur in the database. Which type of data binding would be suitable for this scenario, and why?
- Two-way data binding
- One-way data binding
- Observer pattern
- Three-way data binding
The correct option is Observer pattern. In this scenario, where real-time updates are needed in the UI, the Observer pattern would be suitable. The Observer pattern allows objects to subscribe to changes in other objects and receive notifications when those changes occur. This enables real-time updates in the UI whenever changes happen in the database, ensuring synchronization between the database and the UI. Two-way data binding allows updates from UI to data source and vice versa, but it might not provide real-time updates. One-way data binding only updates the UI from the data source, and Three-way data binding is not a standard concept in ADO.NET.
To add a new row to a DataTable in a dataset, you typically use the ___________ method.
- Insert
- Create
- Append
- Add
The correct option is "Add". When adding a new row to a DataTable in a dataset, the common method used is the Add method of the DataRow collection.
Data binding can simplify UI development by automatically synchronizing ___________ and data source.
- UI controls
- UI elements
- User interface
- Presentation components
The correct option is UI controls. Data binding automatically synchronizes the data displayed by UI controls with data stored in a data source, such as a database or a collection. By binding UI controls directly to data sources, developers can simplify UI development and ensure that the user interface reflects changes in the underlying data automatically.
In ADO.NET Entity Framework, which attribute is commonly used to specify the table to which an entity should be mapped?
- DatabaseTable
- Entity
- MappingTable
- Table
Table
What is distributed transaction management in ADO.NET, and when might it be necessary?
- Coordinates transactions within a single database.
- Ensures data consistency within a single database.
- Facilitates transactions across multiple databases or systems.
- Manages concurrent transactions within a single application.
Distributed transaction management in ADO.NET allows for transactions to span multiple databases or systems, ensuring data consistency across them. This becomes necessary in scenarios where data needs to be updated or retrieved from multiple sources, and maintaining integrity across these sources is crucial.
In Entity Framework, what is a DbSet?
- A collection-like object representing a table in the database that can be queried and modified
- A database context class that represents the connection to the database
- A query language used to retrieve data from the database
- An attribute used to specify the primary key of an entity class
In Entity Framework, a DbSet represents a collection-like object that corresponds to a table in the database. It allows developers to query and manipulate data in that table using LINQ queries and methods provided by Entity Framework. Each DbSet property in a DbContext represents a specific entity type and corresponds to a table in the underlying database.