Node Buffer To String

This paper is an excerpt from the book "The Authoritative Guide to Hadoop", published by Tsinghua University Press, which is the author of Tom White, the School of Data Science and engineering, East China Normal University. This book begins with the origins of Hadoop, and integrates theory and practice to introduce Hadoop as an ideal tool for high-performance processing of massive datasets. The book consists of 16 chapters, 3 appendices, covering topics including: Haddoop;mapreduce;hadoop Distributed file system; Hadoop I/O, MapReduce application Open ...

This article is my second time reading Hadoop 0.20.2 notes, encountered many problems in the reading process, and ultimately through a variety of ways to solve most of the. 　　Hadoop the whole system is well designed, the source code is worth learning distributed students read, will be all notes one by one post, hope to facilitate reading Hadoop source code, less detours. 1 serialization core Technology The objectwritable in 0.20.2 version Hadoop supports the following types of data format serialization: Data type examples say ...

1. HQueue profile HQueue is a set of distributed, persistent message queues developed by hbase based on the search web crawl offline Systems team. It uses htable to store message data, HBase coprocessor to store the original keyvalue data in the message data format, and encapsulates the HBase client API for message access based on the HQueue client API. HQueue can be effectively used in the need to store time series data, as MAPR ...

I have been unable to tolerate the slow pace of progress in programming learning, but I am always very inefficient learning, so from now on, in this series of blogs, accumulated record in the process of programming experience and reflection, hoping to really let themselves grow up quickly. Make up your mind, be patient, focus on the present, and be firm in your fear. The best way to learn other people's code is to step into the program to debug, understand the general framework and process, and then delve into the C language strlen () trap strlen () the role is to take ...

There is a concept of an abstract file system in Hadoop that has several different subclass implementations, one of which is the HDFS represented by the Distributedfilesystem class. In the 1.x version of Hadoop, HDFS has a namenode single point of failure, and it is designed for streaming data access to large files and is not suitable for random reads and writes to a large number of small files. This article explores the use of other storage systems, such as OpenStack Swift object storage, as ...

The REST service can help developers to provide services to end users with a simple and unified interface. However, in the application scenario of data analysis, some mature data analysis tools (such as Tableau, Excel, etc.) require the user to provide an ODBC data source, in which case the REST service does not meet the user's need for data usage. This article provides a detailed overview of how to develop a custom ODBC driver based on the existing rest service from an implementation perspective. The article focuses on the introduction of ODBC ...

Hadoop streaming is a multi-language programming tool provided by Hadoop that allows users to write mapper and reducer processing text data using their own programming languages such as Python, PHP, or C #. Hadoop streaming has some configuration parameters that can be used to support the processing of multiple-field text data and participate in the introduction and programming of Hadoop streaming, which can be referenced in my article: "Hadoop streaming programming instance". However, with the H ...