In Go's database/sql package, what method is used to begin a transaction?
- BeginTx
- StartTransaction
- InitiateTransaction
- CreateTransaction
In Go's database/sql package, the method used to begin a transaction is BeginTx. This method is used to initiate a new database transaction with the provided transaction options. It returns a Tx transaction object that represents the started transaction. Transactions are essential for maintaining data consistency and integrity in database operations, especially when dealing with multiple concurrent requests or complex data manipulations.
Suppose you're writing a critical system component in Go. How would you use 'defer' to ensure proper resource cleanup?
- Defer is used to delay the execution of a function until all other statements in the function have been evaluated.
- Defer is used to ensure proper resource cleanup by explicitly releasing resources before the function exits.
- Defer is used to handle errors gracefully by deferring error-checking code to the end of the function.
- Defer is used to schedule a function call to be executed when the surrounding function returns.
In a critical system component, proper resource cleanup is essential to prevent resource leaks and maintain system stability. 'Defer' in Go allows you to schedule functions to be executed when the surrounding function returns, ensuring that critical resources are properly released regardless of how the function exits (whether through normal return, panic, or early return due to error). This pattern helps manage resources efficiently and reduces the likelihood of bugs related to resource management.
How do you pass a pointer to a function in Go?
- Pass the variable normally without any additional operators
- Use the & operator before the parameter when passing the argument to the function
- Use the * operator before the parameter type when declaring the function signature
- Use the * operator before the variable name when passing it to the function
In Go, to pass a pointer to a function, you use the & operator before the variable when passing it as an argument to the function. This allows the function to modify the original value outside its scope by working with its memory address.
What are some common use cases for middleware in Go web applications?
- Authentication and authorization
- Error handling and panic recovery
- Logging and request/response timing
- Rate limiting and caching
Middleware in Go web applications is often used for logging and request/response timing to gather metrics and monitor performance. Additionally, middleware plays a crucial role in implementing authentication and authorization mechanisms, ensuring that only authorized users can access certain endpoints. Other common use cases include implementing rate limiting to prevent abuse of resources and caching to improve performance by storing frequently accessed data.
In database migration, what does the term 'up' typically signify?
- Applying migrations to update the database schema
- Connecting to a database
- Creating a new database
- Rolling back migrations
In database migration, the term 'up' typically signifies applying migrations to update the database schema. This involves executing scripts or commands to add or modify tables, columns, indexes, or constraints in the database to reflect changes in the application's data model or requirements.
_______ is a metric that indicates the percentage of lines of code executed by the test suite.
- Code Coverage
- Test Analysis
- Test Coverage
- Test Quality
Test Coverage
What is used in Go to achieve concurrency?
- Channels
- Goroutines
- Mutexes
- Pointers
Go uses channels to achieve concurrency by facilitating communication and synchronization between goroutines.
You can specify the number of iterations for benchmarking using the _______ flag.
- -bench
- -count
- -iterations
- -n
The correct answer is "-n". In Go, when executing benchmarks, the -n flag is used to specify the number of iterations for benchmarking. This flag allows developers to control the duration and accuracy of benchmarking tests by adjusting the number of iterations performed. By tweaking this parameter, developers can obtain more precise performance measurements for their code.
The _______ data type in Go is an alias for float64.
- byte
- float32
- int
- rune
In Go, the _____ data type is an alias for float64, which is a 64-bit IEEE 754 floating-point number. This data type is commonly used to represent decimal numbers with floating-point precision.
Gorm provides the _______ function to execute raw SQL queries directly.
- Exec
- Query
- Raw
- Scan
Gorm provides the Exec function to execute raw SQL queries directly. This function is commonly used when you need to execute complex SQL queries or perform database operations that are not supported by Gorm's high-level abstractions. With Exec, you can directly execute SQL statements and handle the results accordingly.