Label:Spark Learning five: Spark SQLtags (space delimited): Spark
Spark learns five spark SQL
An overview
Development history of the two spark
Three spark SQL and hive comparison
Quad
.
Built-in UDF (custom function)
Class SQL query, which is converted to mapreduce execution.
HIVEQL is not fully compatible with the SQL-92 standard:1) It supports multirow Insert function and CREATE TABLE function through select;2) Only basic indexing function is supported;3) does not support transactional and materialized view functions;4) Only limited subquery function is supportedinside Hive, the HIVEQL statement is converted by the compiler to the MapReduce (directed acyclic graph) rel
Spark StreamingSpark streaming uses the spark API for streaming calculations, which means that streaming and batching are done on spark. So you can reuse batch code, build powerful interactive applications using Spark streaming, and not just analyze data.
Spark Streaming Ex
The task scheduling system for Spark is as follows:From the Chinese Academy of Sciences to see the cause rddobject generated DAG, and then entered the Dagscheduler stage, Dagscheduler is the state-oriented high-level scheduler, Dagscheduler the DAG split into a lot of tasks, Each group of tasks is a state, whenever encountering shuffle will produce a new state, you can see a total of three state;dagscheduler need to record those rdd is deposited into
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This article will give a brief review of the origins of the quasi-Newton method L-BFGS, and then its implementation in Spark mllib for source code reading.Mathematical Principles of the quasi-Newton Method
Code Implementation
The regularization method used in the L-BFGS algorithm is squaredl2updater.
The breezelbfgs function in the breeze library of the scalanlp member
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The previous blog shows how to modify the source code to view the call stack. Although it is also very practical, compilation is required for every modification, which takes a lot of time and is inefficient, it is also an invasive modification that is not elegant. This article describes how to use intellij idea to track and debug spark source code.Prerequisites
This document a
The spark version tested in this article is 1.3.1Spark Streaming programming Model:The first step:A StreamingContext object is required, which is the portal to the spark streaming operation, and two parameters are required to build a StreamingContext object:1, Sparkconf object: This object is configured by the Spark program settings, such as the master node of th
Content:1, the traditional spark memory management problem;2, Spark unified memory management;3, Outlook;========== the traditional Spark memory management problem ============Spark memory is divided into three parts:Execution:shuffles, Joins, Sort, aggregations, etc., by default, spark.shuffle.memoryfraction default i
transformation processing, the contents of the dataset are changed, the dataset A is converted to DataSet B, and the contents of the dataset are then normalized to a specific value after action has been processed. Only if there is an action on the RDD, all operation on the RDD and its parent RDD will be submitted to cluster for real execution.From code to dynamic running, the components involved are as shown.New Sparkcontext ("spark://...", "MyJob"
For more than 90% of people who want to learn spark, how to build a spark cluster is one of the greatest difficulties. To solve all the difficulties in building a spark cluster, jia Lin divides the spark cluster construction into four steps, starting from scratch, without any pre-knowledge, covering every detail of the
Label:Scenario: Use spark streaming to receive the data sent by Kafka and related query operations to the tables in the relational database;The data format sent by Kafka is: ID, name, Cityid, and the delimiter is tab.1 Zhangsan 12 Lisi 13 Wangwu 24 3The table city structure of MySQL is: ID int, name varchar1 BJ2 sz3 shThe results of this case are: Select S.id, S.name, S.cityid, c.name from student S joins C
Provides various official and user release code examples. For code reference, you are welcome to exchange and learn about spark grassland system development, spark grassland system source code, distribution system micro-distribution, it is a three-level distribution mall based on the public platform. The three-level distribution should achieve an infinite loop model, and an innovation of the enterprise mark
3, hands-on generics in Scalageneric generic classes and generic methods, that is, when we instantiate a class or invoke a method, you can specify its type, because Scala generics and Java generics are consistent and are not mentioned here. 4, hands on. Implicit conversions, implicit parameters, implicit classes in Scalaimplicit conversion is one of the key points that many people learn about Scala, which is the essence of Scala:Let's take a look at the example of hidden parameters:
The
3, hands-on generics in Scala generic generic classes and generic methods, that is, when we instantiate a class or invoke a method, you can specify its type, because Scala generics and Java generics are consistent and are not mentioned here. 4, hands on. Implicit conversions, implicit parameters, implicit classes in Scala Implicit conversion is one of the key points that many people learn about Scala, which is the essence of Scala: Let's take a look at the example of hidden parameters:
Http://spark.apache.org/docs/1.2.1/streaming-programming-guide.htmlHow to shard data in sparkstreamingLevel of Parallelism in Data processingCluster resources can be under-utilized if the number of parallel tasks used on any stage of the computation are not high E Nough. For example, for distributed reduce operations like reduceByKey reduceByKeyAndWindow and, the default number of parallel tasks are controlled by The spark.default.parallelism configuration property. You can pass the level of par
configuration file are:
Run the ": WQ" command to save and exit.
Through the above configuration, we have completed the simplest pseudo-distributed configuration.
Next, format the hadoop namenode:
Enter "Y" to complete the formatting process:
Start hadoop!
Start hadoop as follows:
Use the JPS command that comes with Java to query all daemon processes:
Start hadoop !!!
Next, you can view the hadoop running status on the Web page used to monitor the cluster status in hadoop. The specific pa
There is a simple demo of spark-streaming, and there are examples of Kafka successful running, where the combination of both, is also commonly used one.
1. Related component versionFirst confirm the version, because it is different from the previous version, so it is necessary to record, and still do not use Scala, using Java8,spark 2.0.0,kafka 0.10.
2. Introduction of MAVEN PackageFind some examples of a c
The Spark standalone uses the Master/slave architecture, which includes the following classes:
Class: Org.apache.spark.deploy.master.Master Description: Responsible for the entire cluster of resource scheduling and application management. Message type: Receives messages sent by worker 1. Registerworker 2. Executorstatechanged 3. Workerschedulerstateresponse 4. Heartbeat messages sent to the worker 1. Registeredworker 2. Registerworkerfailed 3. Reco
The latest virtualization technology of docker cloud computing is gradually becoming the standard of paas lightweight virtualization technology.As an open-source application container engine, docker does not rely on any language, framework, or system, docker using the sandbox mechanism allows developers to package their applications into portable containers and deploy them on all mainstream Linux/Unix systems.This course will go deep into the essence and inside story of docker, from the depth of
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