still be used in the 1.5.1 version, and the actual execution process is SqlContext Createdataframe, it is important to note that a parameter samplingration, whose default value is None, will discuss its specific role later. Here we only consider the case where the data type is inferred from the RDD, i.e. isinstance (data, RDD) is true, the code execution process goes to Sqlcontext_createfromrdd: from the
based on prefix and suffix: "Prefix-time_in_ms[.suffix]".
Saveashadoopfiles (prefix, [suffix]): Saves Dstream as a Hadoop file, and the file naming conventions for each interval batch are based on prefix and suffix:: " Prefix-time_in_ms[.suffix] ".
Foreachrdd (func): The most common output operation that can apply a function _fun_ to each RDD generated from the data flow. Typically _fun_ saves data from each
algorithm. Feature engineering is extremely dependent in the type of use case and potential data sources.(Reference learning Spark)Looking depth at the credit card fraud example for feature engineering, we goal is to distinguish normal card USA GE from fraudulent card usage.
Goal:we is looking for someone using the card other than the cardholder
Strategy:we want to design features to measure the differences between recent and historical
fromoperatorImportItemgetter#Itemgetter used to go to the key in Dict, eliminating the use of lambda functions fromItertoolsImportGroupBy#Itertool also contains a number of other functions, such as combining multiple lists together. d1={'name':'Zhangsan',' Age': 20,'Country':' China'}d2={'name':'Wangwu',' Age': 19,'Country':'USA'}d3={'name':'Lisi',' Age': 22,'Country':'JP'}d4={'name':'Zhaoliu',' Age': 22,'Country':'
.
1. Install the pymysql Module
pip3 install pymysql
2. Connect to the database and insert data instances
Import pymysql # generate an instance and connect to the database zclconn = pymysql. connect (host = '2017. 0.0.1 ', user = 'root', passwd = 'root', db = 'zcl') # generate a cursor. The current instance status is cur = conn. cursor () # insert data reCount = cur.exe cute ('insert into students (name, sex, age, tel, nal) values (% s, % s) ', ('jack', 'Man', 25, 1351234, "CN") reCount = cur.ex
:0.13zookeeper:3.4.5kafka:2.9.2-0.8.1 Other tools: SecureCRT, WinSCP, VirtualBox, etc.2. Introduction to the contentThis course focuses on Scala programming, Hadoop and Spark cluster Setup, spark core programming, spark kernel source depth profiling, spark performance tuning, Spark SQL, spark streaming. The main features of this course include: 1, code-driven to explain the various technical points of spark (absolutely not according to the PPT theory), 2, on-site hands-on drawings to explain the
Core components of the spark Big data analytics frameworkThe core components of the Spark Big Data analysis framework include RDD memory data structures, streaming flow computing frameworks, Graphx graph computing and mesh data mining, Mllib machine Learning Support Framework, Spark SQL data Retrieval language, Tachyon file system, Sparkr compute engine and other major components. Here is a simple introduction.A.
1.map,flatmap,filter uses Scala's internal implementation.2.cogroup,intersection,join,leftouterjoin,rightouterjoin,fullouterjoinrdd1:[, (2,3,4)]rdd2:[(1,3,5), (2,4,6)]Rdd1.cogroup (RDD2)For RDD1 calls cogroup:rdd1->cogroup (RDD2)->cogrouprdd (RDD1,RDD2),mapvalues (), MappartitionsrddCogroup first uses RDD1 and RDD2 to new a cogrouprdd, and then Cogrouprdd generates mapvalues on this mappartitionsrdd call.Implementation of the 2.1intersectionmap ()->mappartitionsrdd->cogroup ()->cogrouprdd->mapva
: RDDRDD (Resilient distributed Datasets), Chinese called Elastic distributed datasets, is a read-only, partitioned collection of records on top of a distributed file system. The RDD is stored in memory, and the operations in the compute task of Spark are also based on the RDD. The read-only nature of the RDD means that its state is immutable and is generally non
It is believed that many people will encounter Task not serializable when they start using spark, most of which are caused by calling an object that cannot be serialized in the RDD operator. Why must the objects in the incoming operator be serialized? This is going to start with spark itself, Spark is a distributed computing framework, the RDD (resilient distributed Datasets, Elastic distributed dataset) is
ArticleDirectory
Based on Spark-0.4 and Hadoop-0.20.2
Spark-0.4 based and Hadoop-0.20.21. kmeans
Data: self-generated 3D data, which is centered around the eight vertices of a square
{0, 0, 0}, {0, 10, 0}, {0, 0, 10}, {0, 10 },
{10, 0, 0}, {10, 0, 10}, {10, 10, 0}, {10, 10}
Point number
189,918,082 (0.1 billion million 3D points)
Capacity
10 GB
HDFS location
/User/lijiexu/kmeans/Square-10GB.txt
ProgramLogic:
Spark Partition Details! DT Big Data Dream Factory Liaoliang teacher personally explain!Http://www.tudou.com/home/_79823675/playlist?qq-pf-to=pcqq.groupWhat is the difference between a shard and a partition?Sharding is from the point of view of the data, the partition is calculated from the point of view , actually are from the large state, split into small.Second, spark partition understandingThe RDD, as a distributed dataset, is distributed across m
The spark ecosystem, also known as Bdas (Berkeley data Analytics stack), is a platform designed by the Berkeley Apmlab Lab to showcase big data applications through large-scale integration between algorithms (algorithms), Machines (machines), and people (people). The core engine is spark, which is based on the elastic distributed data set, or RDD. Through the spark ecosystem, Amplab uses resources such as big data, cloud computing, communications, and
repetitive and tedious work, which affects the popularization of the paddle platform, so that many teams in need cannot use the depth learning technology.
To solve this problem, we designed the spark on paddle architecture, coupled spark and paddle to make paddle a module of spark. As shown in Figure 3, model training can be integrated with front-end functions, such as feature extraction through RDD data transfer, without HDFS data diversion. Thus, t
Yesterday interview was asked the difference between the cache and persist, then only remember that one of the calls to another, but did not answer the difference between the two, so come back to see the source code, is to find out the difference between them.
Both the cache and the persist are used for caching an RDD so that it does not need to be recalculated in the process of subsequent use, which can significantly save program run time. the differ
()# # NAME (age + 1)# # Michael NULL# # Andy# # Justin# Select people older thanDf.filter (df[' age '] > +). Show ()# # Age name# # Andy# Count People by ageDf.groupby ("Age"). Count (). Show ()# # Age Count# # null 1# 1# 14. Using programming to execute SQL queriesSqlContext can use programming to execute SQL queries and return dataframe.fromimport SQLContextsqlContext = SQLContext(sc)df = sqlContext.sql("SELECT * FROM table")5. Interacting with the RDDThere are two ways to convert an
Createdataframe, it is important to note that a parameter samplingration, whose default value is None, will discuss its specific role later. Here we only consider the case where the data type is inferred from the RDD, i.e. isinstance (data, RDD) is true, the code execution process goes to Sqlcontext_createfromrdd: from the above code invocation logic can be seen, the schema is none, the code execution
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