St Louis
-
3 min readThe default scheme configuration in Hadoop is located in the core-site.xml file. This file can be found in the conf directory within the Hadoop installation directory. The scheme configuration specifies the default file system scheme to be used by Hadoop, such as hdfs:// for Hadoop Distributed File System. By default, this file contains properties that define the default setting for various Hadoop components, including the file system scheme, replication factor, and block size.
-
6 min readTo create a caching object factory in Rust, you can start by defining a struct that represents the caching object. This struct should contain a HashMap or any other data structure to store the cached objects.Next, implement methods for adding objects to the cache, retrieving objects from the cache, and clearing the cache if needed. Make sure to handle concurrency issues, such as using locks or atomic operations to ensure thread safety when accessing the cache.
-
8 min readTo efficiently join two files using Hadoop, you can use the MapReduce programming model. Here's a general outline of how to do it:First, you need to define your input files and the keys you will use to join them. Each line in the input files should have a key that will be used to match records from both files. Write a Mapper class that will process each line from both input files and emit key-value pairs. The key should be the join key, and the value should be the full record.
-
6 min readIn Rust, understanding dereferencing and ownership is crucial for writing safe and efficient code. Dereferencing in Rust refers to accessing the value pointed to by a reference or pointer. This is done using the * operator.Ownership in Rust is a unique concept that enforces strict rules about how memory is managed. Each value in Rust has a unique owner, and there can only be one owner at a time.
-
3 min readMap-side sort time in Hadoop refers to the time taken for the sorting phase to be completed on the mappers during a MapReduce job. This time is crucial as it directly impacts the overall performance and efficiency of the job. To find the map-side sort time in Hadoop, you can monitor the job logs and look for information related to the shuffle and sort phases. By analyzing these logs, you can determine the time taken for sorting on the mapper side.
-
5 min readTo use the mongodb::cursor in Rust, you first need to connect to a MongoDB database using the mongodb crate. Once you have established a connection, you can use the collection method to access a specific collection in the database. You can then use the find method to create a query that will return a cursor to iterate over the results.
-
5 min readTo install Hadoop on Windows 8, you will need to follow several steps. First, download the Hadoop distribution from the Apache website. Next, extract the downloaded file to a specific directory on your local machine. Then, set up the necessary environment variables such as JAVA_HOME and HADOOP_HOME. After that, configure the Hadoop XML files according to your system specifications. Finally, start the Hadoop services by running the appropriate scripts.
-
5 min readIn Rust, passing a vector as a parameter is similar to passing any other type of variable. You can simply declare the function parameter with the vector type specified in the function signature. For example, if you have a function that takes a vector of integers as a parameter, you can define the function like this: fn print_vector(v: Vec<i32>) { for num in v { println!("{}", num); } } fn main() { let numbers = vec.
-
8 min readHBase and HDFS are both components of the Hadoop ecosystem, but they serve different purposes. HDFS (Hadoop Distributed File System) is a distributed file system used for storing large volumes of data in a distributed manner across multiple nodes in a Hadoop cluster. It provides high throughput and fault tolerance for storing and processing Big Data.On the other hand, HBase is a NoSQL database that runs on top of HDFS and provides random, real-time read/write access to Big Data.
-
4 min readTo extract strings from a PDF file in Rust, you can use the pdf-extract crate. This crate provides functionality to extract text strings from a PDF file. You can start by adding the pdf-extract crate to your Cargo.toml file. Then, you can use the crate's functionality to extract text from the PDF file by following the provided documentation and examples. It allows you to read the text content of the PDF document and extract the strings you need for further processing in your Rust program.
-
5 min readData encryption in Hadoop is essential to ensure the security and confidentiality of sensitive information stored in the system. There are multiple ways to implement data encryption in Hadoop, including encryption at rest and encryption in transit.To encrypt data at rest, you can utilize tools such as HDFS Transparent Encryption, which encrypts data blocks before they are written to disk. This ensures that data remains encrypted while stored on the Hadoop Distributed File System (HDFS).