The SqlDataAdapter is used to fill a ________ with data from a database.
- DataGrid
- DataReader
- DataSet
- DataTable
The SqlDataAdapter is primarily used to populate a DataSet with data retrieved from a database. It acts as a bridge between the database and the DataSet, allowing data to be fetched and stored in a structured format.
Which ADO.NET control is commonly used for data binding in Windows Forms applications?
- ComboBox
- DataGridView
- ListBox
- TextBox
The DataGridView control is extensively used for data binding in Windows Forms applications. It provides a powerful and flexible way to display and manipulate tabular data, offering features such as sorting, filtering, and editing. With its rich functionality, the DataGridView control simplifies the process of presenting data from a data source to users in a structured format.
Which ADO.NET class or object is commonly used to create parameterized queries?
- SqlCommand
- SqlConnection
- SqlDataAdapter
- SqlDataReader
The SqlCommand class in ADO.NET is commonly used to create parameterized queries. It allows developers to define parameter placeholders in SQL queries and then assign values to these parameters programmatically, helping to prevent SQL injection attacks and improve query performance.
The ObjectContext class is responsible for ___________ with the underlying database.
- Connecting
- Interfacing
- Mapping
- Querying
The ObjectContext class in Entity Framework is responsible for interfacing with the underlying database. It manages connections, tracks changes, and orchestrates queries and updates to the database. It acts as a bridge between the application and the database, providing a set of methods and properties to interact with entity data models and database objects effectively.
The use of ___________ can help in caching query results and improving query performance.
- AsNoTracking()
- FirstOrDefault()
- Include()
- ToList()
The correct answer is AsNoTracking(). By using AsNoTracking(), Entity Framework Core does not keep track of the entities retrieved from the database, which can help in caching query results and improving query performance, especially in read-only scenarios where entities are not modified.
What is the primary purpose of the DbContext class in Entity Framework?
- To define the mapping between entity classes and database tables
- To define the structure of the database and manage migrations
- To handle database transactions and concurrency
- To represent a session with the database and provide APIs for querying and saving data
The DbContext class in Entity Framework serves as the primary entry point for interacting with the database. It represents a session with the database and provides APIs for querying and saving data. DbContext also manages the connection to the database, tracks changes to entities, and facilitates change tracking, which is essential for implementing features like lazy loading and change tracking.
In ADO.NET, what is the primary role of the DataAdapter?
- Executes SQL commands and returns a result set
- Provides a forward-only, read-only cursor for accessing data
- Represents a connected architecture for interacting with a database
- Retrieves data from the database and populates a DataSet
The primary role of the DataAdapter in ADO.NET is to retrieve data from the database and populate a DataSet. It acts as a bridge between the database and the DataSet, facilitating communication and data transfer.
The Entity Framework enables developers to work with data using a ___________-first approach.
- Code
- Data
- Database
- Model
The Entity Framework enables developers to work with data using a code-first approach. In this approach, you define your model classes first, and then the database schema is generated based on those classes.
Data binding to list controls like ListBox and DropDownList is often used to present data to users in a ___________ format.
- Tabular
- Hierarchical
- Linear
- Sequential
The correct answer is "Linear." Data binding to list controls like ListBox and DropDownList usually presents data to users in a linear format, where each data item is displayed one after the other, typically in a single column. This format is suitable for displaying lists of options or items.
When using the UPDATE command, you typically specify a ___________ clause to identify the rows to be updated.
- FROM
- JOIN
- SET
- WHERE
In SQL, the UPDATE command is used to modify existing records in a table. The WHERE clause is used to specify which rows should be updated based on certain conditions. For example, you might use WHERE to update only the rows where a certain column equals a specific value.