________ is a NoSQL database that is designed for horizontal scalability and distributed architecture.
- Cassandra
- Couchbase
- MongoDB
- Redis
Cassandra is a NoSQL database designed for horizontal scalability and distributed architecture. It is suitable for handling large amounts of data across multiple commodity servers. MongoDB, Redis, and Couchbase are also NoSQL databases but may have different design considerations.
n regression analysis, the _______ measures the strength and direction of a linear relationship between two variables.
- Correlation Coefficient
- Intercept
- R-squared
- Slope
In regression analysis, the correlation coefficient measures the strength and direction of a linear relationship between two variables. It ranges from -1 to 1, where 1 indicates a perfect positive linear relationship, -1 indicates a perfect negative linear relationship, and 0 indicates no linear relationship.
In SQL, how do you select all columns from a table named 'Customers'?
- SELECT * FROM Customers
- SELECT ALL FROM Customers
- SELECT COLUMNS FROM Customers
- SELECT DATA FROM Customers
To select all columns from a table named 'Customers' in SQL, you use the syntax: SELECT * FROM Customers. The asterisk (*) is a wildcard character that represents all columns.
In hypothesis testing, the _______ value is used to determine the statistical significance of the results.
- Alpha
- Beta
- Confidence Interval
- P-value
The P-value is used in hypothesis testing to assess the evidence against a null hypothesis. A small P-value suggests that the null hypothesis is unlikely, leading to the rejection of the null hypothesis in favor of the alternative hypothesis.
In a situation where data consistency is critical, what feature of a DBMS should be prioritized?
- ACID Compliance
- Indexing
- Query Performance
- Sharding
Data consistency is ensured by ACID (Atomicity, Consistency, Isolation, Durability) compliance. ACID compliance guarantees that database transactions are processed reliably and consistently, which is crucial in scenarios where data consistency is a top priority.
For a global e-commerce platform that requires high availability and scalability, what kind of database architecture would be most appropriate?
- Centralized Database
- Distributed Database
- NoSQL Database
- Relational Database
A global e-commerce platform with high availability and scalability requirements would benefit from a Distributed Database architecture. Distributed databases distribute data across multiple servers or locations, ensuring both availability and scalability for a large user base and global operations.
In a situation where you need to merge two datasets in R using dplyr, but the key columns have different names, how would you approach this?
- bind_rows()
- left_join()
- merge() with by parameter
- rename()
To merge datasets in dplyr with different key column names, you can use the rename() function to rename the key columns in one or both datasets, ensuring they match. This allows you to then use the standard left_join() or other merge functions.
In a project involving customer feedback analysis, which preprocessing step would you prioritize to handle various slangs and abbreviations in the feedback texts?
- Lemmatization
- Stopword Removal
- Text Normalization
- Tokenization
Text normalization is essential for handling slangs and abbreviations. It involves steps like converting text to lowercase, removing special characters, and standardizing abbreviations to ensure uniformity in the data.
An API key is used as a form of _________ to control access to an API.
- Authentication
- Authorization
- Encryption
- Validation
An API key is used as a form of authentication to control access to an API. It serves as a unique identifier for a user or application and helps ensure that only authorized entities can access the API's resources.
In distributed computing, what kind of data structure is often used for managing scalable, partitioned, and replicated data?
- AVL Tree
- Bloom Filter
- Distributed Hash Table (DHT)
- Red-Black Tree
Distributed Hash Tables (DHTs) are commonly used in distributed computing to manage scalable, partitioned, and replicated data. DHTs provide a decentralized way to distribute and locate data across multiple nodes in a network, ensuring efficient access and fault tolerance.