What strategy does Parquet use to enhance query performance on columnar data in Hadoop?
- Compression
- Data Encoding
- Indexing
- Predicate Pushdown
Parquet enhances query performance through Predicate Pushdown. This strategy involves pushing parts of the query execution directly to the storage layer, reducing the amount of data that needs to be processed by the query engine. This is particularly effective for columnar data storage, like Parquet, where only relevant columns are read during query execution.
For a company dealing with sensitive information, which Hadoop component should be prioritized for enhanced security during cluster setup?
- DataNode
- JobTracker
- NameNode
- ResourceManager
For enhanced security in a Hadoop cluster dealing with sensitive information, prioritizing the security of the NameNode is crucial. The NameNode contains metadata and information about data locations, making it a potential target for security threats. Securing the NameNode helps safeguard sensitive data in the cluster.
Advanced debugging in Hadoop often involves analyzing ____ to diagnose issues in job execution.
- Configuration Files
- Job Scheduling
- Log Files
- Task Tracker
Advanced debugging in Hadoop often involves analyzing Log Files to diagnose issues in job execution. Log files contain valuable information about the steps taken during job execution, helping developers identify and resolve issues in the Hadoop application.
In a case where sensitive data is processed, which Hadoop security feature should be prioritized for encryption at rest and in transit?
- Hadoop Access Control Lists (ACLs)
- Hadoop Key Management Server (KMS)
- Hadoop Secure Sockets Layer (SSL)
- Hadoop Transparent Data Encryption (TDE)
For encrypting sensitive data at rest and in transit, Hadoop Transparent Data Encryption (TDE) is a crucial security feature. TDE encrypts data stored in HDFS, adding an extra layer of protection, and ensures that data transferred between nodes is encrypted, safeguarding it from unauthorized access.
Which component of Apache Pig translates scripts into MapReduce jobs?
- Pig Compiler
- Pig Engine
- Pig Parser
- Pig Server
The component of Apache Pig that translates scripts into MapReduce jobs is the Pig Compiler. It takes Pig Latin scripts as input and converts them into a series of MapReduce jobs that can be executed on a Hadoop cluster for data processing.
Apache Spark's ____ feature allows for dynamic allocation of resources based on workload.
- ClusterManager
- DynamicExecutor
- ResourceManager
- SparkAllocation
Apache Spark's ClusterManager feature allows for dynamic allocation of resources based on workload. The ClusterManager dynamically adjusts the resources allocated to Spark applications based on their needs, optimizing resource utilization.
In Hadoop, ____ is a key aspect of managing and optimizing cluster performance.
- Data Encryption
- Data Replication
- Data Serialization
- Resource Management
Resource management is a key aspect of managing and optimizing cluster performance in Hadoop. Tools like YARN (Yet Another Resource Negotiator) play a crucial role in efficiently allocating and managing resources for running applications in the Hadoop cluster.
____ is a distributed NoSQL database that integrates with the Hadoop ecosystem for efficient data storage and retrieval.
- Cassandra
- CouchDB
- HBase
- MongoDB
HBase is a distributed NoSQL database that integrates with the Hadoop ecosystem for efficient data storage and retrieval. It is designed to handle large volumes of sparse data and is well-suited for random, real-time read/write access to Hadoop data.
What strategies can be used in MapReduce to optimize a Reduce task that is slower than the Map tasks?
- Combiner Functions
- Data Sampling
- Input Splitting
- Speculative Execution
One strategy to optimize a Reduce task that is slower than the Map tasks is Speculative Execution. In this approach, multiple instances of the same Reduce task are launched on different nodes, and the one that finishes first is accepted, reducing the overall job completion time.
Which file in Hadoop configuration specifies the number of replicas for each block in HDFS?
- core-site.xml
- hdfs-site.xml
- mapred-site.xml
- yarn-site.xml
The hdfs-site.xml file in Hadoop configuration specifies the number of replicas for each block in HDFS. This configuration is essential for ensuring fault tolerance and data reliability by controlling the replication factor of data blocks across the cluster.