Which caching strategy is suitable for frequently updated content?
- Content-based caching
- Randomized caching
- Time-based caching
- User-based caching
Content-based caching is suitable for frequently updated content. This strategy depends on the content itself, ensuring that the cache is refreshed whenever the content changes.
What does the term "NoSQL" signify in database management?
- NewSQL
- Non-Simple Query Language
- Non-Specific Query Language
- Not Only SQL
"NoSQL" signifies "Not Only SQL." It represents a class of database management systems that do not strictly adhere to the traditional relational database management system principles.
The command "git reflog" displays a _______ of actions that have been taken in the repository.
- Catalog
- Log
- Record
- Timeline
The command "git reflog" displays a log of actions that have been taken in the repository. It provides a reference log, showing the history of HEAD movements, making it useful for recovering lost commits or branches.
What is the difference between a JOIN and a UNION in SQL?
- JOIN combines rows from two or more tables based on a related column
- JOIN is used for vertical merging
- UNION combines the results of two or more SELECT statements
- UNION is used for horizontal merging
In SQL, a JOIN combines rows from two or more tables based on a related column, while a UNION combines the results of two or more SELECT statements. JOIN operates vertically by merging rows, while UNION operates horizontally by combining result sets.
A _______ is a data structure that consists of a collection of nodes and edges.
- Graph
- Heap
- Queue
- Tree
A graph is a data structure that consists of a collection of nodes and edges. Nodes represent entities, and edges represent relationships between those entities.
_______ is the ability of an object to take on many forms in OOP.
- Abstraction
- Encapsulation
- Inheritance
- Polymorphism
Polymorphism is the ability of an object to take on many forms. In object-oriented programming (OOP), it allows objects of different types to be treated as objects of a common type, providing flexibility and extensibility in code design.
In a distributed database system, how would you approach query optimization to minimize network latency and improve overall performance?
- Implement only vertical partitioning, Optimize queries centrally, Decrease node communication, Disable encryption on the network
- Implement sharding and partitioning, Use asynchronous communication, Optimize queries locally on each node, Increase the bandwidth of the network
- Increase network latency intentionally, Use only synchronous communication, Disable query caching, Randomly distribute data across nodes
- Use a single centralized database, Minimize the number of nodes, Decrease the network bandwidth, Increase the size of each query
In a distributed database system, optimizing queries involves implementing sharding, partitioning, and using asynchronous communication to minimize network latency. Optimizing queries locally on each node is essential for efficient distributed query processing.
_______ migration involves moving data from one storage system to another without any downtime.
- Live
- Non-disruptive
- Seamless
- Zero-Downtime
Zero-Downtime migration refers to the process of moving data from one storage system to another without any disruption or downtime in services. This ensures continuous operations during the migration.
You're tasked with optimizing a query that retrieves data from a large table. Outline the steps you would take to analyze and optimize the query.
- Analyze query execution plan, Identify and create necessary indexes, Optimize SQL queries, Monitor system resources
- Backup and restore the entire database, Use only subqueries, Disable query caching, Modify the network configuration
- Rebuild the entire database, Delete unnecessary records, Increase server memory, Change database schema
- Use NoSQL instead of SQL, Change server hardware, Reduce database security, Update all records in the table
To optimize a query, you would analyze its execution plan, identify and create necessary indexes, and optimize the SQL queries. Monitoring system resources is crucial to ensuring overall performance improvements.
Which method is used to add elements to the end of an array in JavaScript?
- pop()
- push()
- shift()
- splice()
The push() method in JavaScript is used to add elements to the end of an array. It modifies the original array by adding the specified elements.