Handling data conflicts in ADO.NET involves strategies like ___________ resolution and ___________ resolution.
- Concurrency
- Locking
- Optimistic
- Pessimistic
In ADO.NET, handling data conflicts can be approached using two main strategies: Optimistic concurrency resolution, where the system assumes that conflicts between users are rare, and Pessimistic concurrency resolution, where the system locks data to prevent conflicts.
Parameterized queries help mitigate the risk of ________ attacks.
- Cross-site request forgery
- Cross-site scripting
- Denial-of-Service
- SQL injection
Parameterized queries play a crucial role in mitigating the risk of SQL injection attacks. SQL injection attacks occur when malicious SQL statements are inserted into input fields, potentially allowing attackers to execute unauthorized queries or manipulate data. By using parameterized queries, user input is treated as data rather than executable code, effectively preventing SQL injection by separating SQL logic from user input.
What is the primary purpose of connection pooling in ADO.NET?
- To increase security of database connections
- To minimize the overhead of opening and closing database connections
- To optimize query execution in the database server
- To reduce memory consumption in the application
Connection pooling in ADO.NET primarily aims to minimize the overhead of opening and closing database connections. When connection pooling is enabled, instead of completely closing a connection, it is returned to a pool where it can be reused by subsequent requests, thus reducing the overhead of establishing new connections. This optimization enhances the performance of applications that frequently interact with the database.
Exception handling in non-query command execution involves using ___________ to catch and handle errors.
- if-else statements
- switch-case statements
- try-catch blocks
- while loops
Exception handling in programming involves anticipating and handling errors or exceptional situations that may occur during the execution of code. In many programming languages, including JavaScript and Java, try-catch blocks are commonly used for exception handling. Within a try-catch block, you place the code that you expect might cause an error, and then use catch to handle any resulting exceptions.
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.
Which LINQ operator is used to filter elements in a LINQ to DataSet query?
- From
- OrderBy
- Select
- Where
The Where operator in LINQ to DataSet is used to filter elements based on a specified condition. It allows developers to narrow down the dataset to only include elements that meet certain criteria, similar to the WHERE clause in SQL queries.
What is the purpose of the SqlParameter class when working with stored procedures?
- To compile SQL queries, To optimize database performance, To specify the data type and value of parameters used in a stored procedure, To execute DDL commands
- To define the parameters of a stored procedure, To execute the stored procedure, To handle exceptions in the stored procedure, To close the connection to the database
- To establish a connection to the database, To retrieve data from the database, To update data in the database, To parse SQL queries
- To validate user input, To format output data, To manage database transactions, To encapsulate database connection
The purpose of the SqlParameter class in ADO.NET is to specify the data type and value of parameters used in a stored procedure. This allows you to pass parameters to a stored procedure and execute it with the specified parameter values.
A dataset in ADO.NET can be thought of as an in-memory ___________.
- Database
- Dataset
- Recordset
- Table
In ADO.NET, a dataset represents an in-memory cache of data retrieved from a data source, which can hold multiple tables, relationships, and constraints.
Scenario: You want to update an existing order's shipping address in a SQL Server database using LINQ to SQL. Which LINQ to SQL method or operation is appropriate for this situation?
- Attach
- InsertOnSubmit
- SubmitChanges
- Update
SubmitChanges method is appropriate for updating existing records in a LINQ to SQL data context. After making changes to the object properties, calling SubmitChanges persists those changes to the database. Attach is used to attach existing objects to a data context, not for updates. Update is not a direct method in LINQ to SQL for updating records. InsertOnSubmit is used for inserting new records, not for updating existing ones.