The '_______' function in Go is used to regain control of a panicking goroutine.
- capture
- defer
- panic
- recover
The recover function in Go is used to regain control of a panicking goroutine. It's typically used in deferred functions to handle panics gracefully and to resume normal execution.
How does Go handle cyclic dependencies between packages?
- Go does not support cyclic dependencies between packages.
- Go resolves cyclic dependencies by using package initialization.
- Go resolves cyclic dependencies by using the 'import' keyword.
- Go resolves cyclic dependencies by using the 'require' keyword.
In Go, cyclic dependencies between packages are handled through package initialization. When a package is imported, its init function is called, allowing initialization code to execute before the package is used. This mechanism helps manage cyclic dependencies effectively.
The _______ statement in Go is used to iterate over elements in an array, slice, string, or map.
- for
- if
- switch
- range
The correct option is "range". In Go, the "range" statement is used to iterate over elements in various data structures such as arrays, slices, strings, or maps. It simplifies the process of looping through the elements of these data structures by providing a concise syntax. The "range" statement is versatile and allows iterating over different types of collections, making it a powerful tool for traversal and processing of data in Go programs.
When writing tests in Go, the naming convention for test files typically ends with the suffix _______.
- .go_test
- .test
- .testing
- _test.go
In Go, the convention for naming test files is to append "_test.go" as the suffix to the file name. This helps differentiate test files from regular source code files.
Which package provides a powerful router for HTTP services in Go?
- gorouter
- httprouter
- mux
- router
The correct option is httprouter. The httprouter package in Go offers a highly efficient HTTP request router that matches the incoming requests against a list of registered routes.
You're developing a web application in Go, and you need to execute a SQL query that might return multiple rows. Which method from the database/sql package would you use, and how would you handle the returned rows?
- Exec method; Execute the query and retrieve the result set directly. Use rows.Scan() within a loop to scan each row into variables for processing.
- Prepare method; Prepare the SQL statement, execute it using Query or QueryRow, then scan each row using rows.Scan().
- Query method; Use rows.Next() in a loop to fetch each row one by one, then process each row's data.
- QueryRows method; Iterate over the rows using a loop and scan each row into a struct to process the data.
The correct method to use in this scenario is QueryRows. This method allows executing a SQL query that returns multiple rows. You can iterate over the rows using a loop and scan each row into a struct or variables for further processing.
Explain the concept of capacity and length in slices in Go.
- Capacity and length both represent the maximum number of elements a slice can hold.
- Capacity is the number of elements in the slice and length is the maximum number of elements it can hold.
- Length is the number of elements in the slice and capacity is the maximum number of elements it can hold.
- Length represents the maximum number of elements a slice can hold and capacity represents the number of elements in the slice.
In Go, the length of a slice is the number of elements it contains, and the capacity of a slice is the number of elements in the underlying array, counting from the first element in the slice. The length of a slice can change during execution, but the capacity of a slice remains fixed. Understanding the difference between length and capacity is crucial for efficient memory management in Go programs.
What does the '<<' operator do in Go when used with integers?
- Divides two integers
- Left shifts the bits of an integer
- Multiplies two integers
- Right shifts the bits of an integer
In Go, the '<<' operator performs a left shift operation on the bits of an integer. It moves each bit to the left by a specified number of positions, effectively multiplying the integer by 2 raised to the power of the shift count.
MongoDB uses _______ for defining indexes to improve query performance.
- AVL trees
- B-trees
- Binary Search Trees
- Hashing
MongoDB primarily uses B-trees (balanced trees) for indexing. B-trees are well-suited for disk-based storage systems and efficiently support range queries and updates, enhancing query performance.
Which testing framework in Go provides support for table-driven tests, allowing multiple test cases to be defined in a structured format?
- Ginkgo
- GoConvey
- Testify
- Testify and Ginkgo
Ginkgo is a popular testing framework in Go that offers support for table-driven tests, which allow multiple test cases to be defined in a structured format. This approach enhances test readability and maintenance by separating test cases into clear tables.
Your team is transitioning from a monolithic architecture to microservices, and each service has its own database schema. How would you coordinate database migrations across multiple services to maintain data consistency and minimize downtime?
- Adopt a shared-nothing architecture to isolate database instances for each microservice
- Assign each microservice team the responsibility of managing its database migrations
- Implement a centralized database migration service that coordinates schema changes across all microservices
- Use distributed transactions to synchronize schema changes across microservices
Assigning each microservice team the responsibility of managing its database migrations ensures that changes are aligned with the service's requirements and reduces coordination overhead. Implementing a centralized database migration service might introduce a single point of failure and increase complexity. Distributed transactions can lead to performance issues and tightly couple microservices. Adopting a shared-nothing architecture might provide isolation but doesn't inherently address coordination of schema changes and can increase operational complexity.
The _______ function in Go is used to initialize a new instance of a struct.
- create
- initialize
- make
- new
The new function in Go is used to create a new instance of a struct. It allocates memory for the struct, initializes its fields to their zero value, and returns a pointer to the newly allocated struct instance.