java data type

Java basic data type For the programmer, the data type is the most basic, otherwise in the later learning process will encounter many problems.. It's not bullshit either. Go straight to the subject: Java has big data types: 1. built in data type; 2. Application data type. The built-in data type I unders ...

Posted on Tue, 25 Feb 2020 03:38:29 -0800 by nwoottonn

Fight against new coronavirus - get and save online data

# default_exp getdata # The above line is used to declare the name of this module in nbdev. Must be the first row of the first Cell of the notebook. getdata Description: fight against new coronavirus (4) - acquire and save online data. Function: get data, convert to list format, save to *. c s v file, for subsequent analysis and drawin ...

Posted on Mon, 10 Feb 2020 04:14:33 -0800 by paulb

Detailed explanation of Hive function and actual combat of case list

1. Built in functions of Hive system 1.1 numerical calculation function 1. Rounding function: round Syntax: round(double a)Return value: BIGINTNote: returns the integer value part of double type (following rounding) hive> select round(3.1415926) from tableName; 3 hive> select round(3.5) from tableName; 4 hive> create table tableName a ...

Posted on Wed, 05 Feb 2020 04:14:30 -0800 by AndrewBacca

2. Hive installation tutorial

VX: Data Science Lecture 1. Prepare hive installation package Download the hive installation package according to the 1.1 tutorial 1.1 download hive Download address After opening the download address, click apache-hive-1.2.2-bin.tar.gz as shown below to download 1.2 upload hvie installation package Based on our previous environment installati ...

Posted on Wed, 22 Jan 2020 09:20:36 -0800 by $var

Java serialization 67 - in-depth one-dimensional array, detailed explanation of args parameter in main method

1, Reviewed one-dimensional array, also reviewed the attention of forced type conversion. package com.bjpowernode.java_learning; public class D67_1_GoDeepIntoArrays { public static void main(String[] args) { //Create an array that can store Dog,It can also be stored Cat Animal67[] as = new Animal67[4]; //Assign values ...

Posted on Mon, 06 Jan 2020 07:04:03 -0800 by Fira

Hadoop High Availability Cluster - HA

Prior to Hadoop2.0, Name Node of HDFS had a single point of failure.The so-called HA is highly available (7*24 hours of uninterrupted service).HA is strictly a HA mechanism that should be divided into components: HA of HDFS and HA of YARN.The HDFS HA feature solves a single point of failure by configuring Active/Standby two NameNodes to impleme ...

Posted on Sun, 29 Dec 2019 20:09:25 -0800 by tready29483

How to use CPFS storage volume service in Alibaba cloud ACK cluster

Introduction: CPFS (cloud parallel file system) is a kind of parallel file system. CPFS data is stored in multiple data nodes in the cluster and can be accessed by multiple clients at the same time, so it can provide high IOPS, high throughput and low latency data storage services for large-scale high-performance computer cluster. CPFS detailed ...

Posted on Tue, 24 Dec 2019 23:37:46 -0800 by cemeteryridge

ceph generation capacity expansion 24 hours

Finally spent 24 hours of ceph production environment data migration. Let's record the problems and solutions we have encountered, and then we will have solutions to them. Let's start with an openshift issue. Everyone should be familiar with openshift. Many openshift cloud storage that needs to be mounted is connected to ceph cluster. Under th ...

Posted on Sun, 15 Dec 2019 10:18:01 -0800 by Wave

6. addCacheFile sends small files to map to realize map end join

1, demand When joining large and small tables, you can send the small table to the map side, and then load the small table into memory, so that you can quickly match the join For example: calculate the total amount of each product in each user's shopping list 2, train of thought You can send the product table file in the form of addchefiule to ...

Posted on Sat, 14 Dec 2019 12:51:45 -0800 by mospeed

Full version of user churn warning python machine learning

Organize each version, but the time problem, more or less there will be some version problems, so seriously to write a case of user churn warning. The data we get represents this form. If you need a packet, please give the corresponding mailbox. First, attach the corresponding interpretation results   In this case, we s ...

Posted on Sat, 14 Dec 2019 11:49:28 -0800 by StateGuy