mongodb 3 4 centos 7

#!/usr/bin/env python# Coding:utf-8Import Redef Dealwith (Express): Express.replace ('+-','-') Express.replace ('--','+') returnexpressdef Col_suanshu (exp):if '/' inchexp:a,b= Exp.split ('/') returnStrfloat(a)/float(b))if '*' inchexp:a,b= Exp.split ('*') returnStrfloat(a) *float(b) def get_no_barcate (Express): Express=express.strip ('()') Print ('>>>', Express) whileTrue:ret= Re.search ("-?\d+\.? \d*[*/]-?\d+\.? \d*", Express)ifRet:res=Col_suanshu (Ret.group ()) Express= Ex

create a XXY database and create a collectionmongos> use xxymongos> db.users.insert({"id":1,"name":"zhangsan"})mongos> show dbsCan write multiple messages with circular statementsmongos> for(var i=2;iUse the Sh.status () command to view Shard state information. A value of "partitioned" is false to indicate that the database is not fragmented.mongos> sh.status() //查看数据库分片信息Use the sh.enablesharding ("XXY") command to enable XXY database sharding. Check again to see that the "partitioned

Problem description: there are now n ordered arrays in M groups, such as {1, 2, 3, 4}, {2, 3, 6}, {1, 3, 5, 7 }, select the data smaller than K in these arrays and return this value. Idea: Compare the minimum data selected each time by referring to the process of merging two

动### （4）连接并访问MongoDB/usr/bin/mongo Db.version () #查看版本3.6.6Show DBS; #查看数据库Admin 0.000GBConfig 0.000GBLocal 0.000GB ----------## 三、MongoDB 3.6的基本操作 1. Turn on multi-instance (1) Copy a configuration file to a second instancecp -p /etc/mongod.conf /etc/mongod2.conf## 复制一份配置文件给第二个实例(2) Editing the second instance configuration file and startup par

, you can configure MongoDB to store data on different disk devices to increase write throughput or disk capacity. The default value is false. # It is recommended that you configure the option at the beginning. Directoryperdb = true # disable logs # enable operation logs corresponding to journal to ensure the write persistence and data consistency. The journal directory is created under the dbpath directory. Nojournal = true ## Max connections # maxim

same key" When sorting by key, the MongoDB does not enforce the value of the key, and we also encounter the same key in practice, in which a string is a number in another document, and the document is sorted in any way. In MongoDB, there is a predefined order, from small to large, followed by: (1): Minimum value (2): null (3): Digital (integral type, long intege

Package com; public class test {public static void main (string [] ARGs) {system. out. println (getsteps1 (); system. out. println (">>>>>>>>>>>>>>>>>>>>>>>>>>>>"); system. out. println (test. getsteps (); system. out. println (">>>>>>>>>>>>>>>>>>>>>>>>>>>> ");} public static int getsteps () {// use the minimum public multiple to reduce the number of traversal times. Int I = 1; int step = 2; Boolean maxstep = false; while (true) {system. Out. Print ("" + I + "); If (! Maxstep) {if (I % 2 = 1) {s

" : "3 to 4", "Number" : 4, "LastModified" : new Date("27/11/2012 10:41:34"), "ContactList" : null }, { "_id" : new BinData(3, "N68jDslbU0uvdHJTSq0vIg=="), "Username" : "5", "Password" : "6", "Number" : 7, "LastModified" : new Date(

/mongodb-linux-x86_64-3.2.3.tgz./ TAR-ZXVF mongodb-linux-x86 _64-3.2.3.tgz MV mongodb-linux-x86_64-3.2.3 MongoDB So you can get the final MongoDB folder, inside the file structure is as follows: 　　 The bin folder is the main program directory of

enterprise-class reliability and operational flexibility.The installation of MongoDBMongoDB provides the installation package on the Linux platform, which can be downloaded from the official website. This experiment installs the latest version of MongoDB 4.0.0 on CentOS 7, the package used is: mongodb-linux-x86_64-rhe

CentOS 7 server configuration-install MongoDB, centosmongodb# Download the MongoDB source file: wget unzip-zxvf mongodb-linux-x86_64-rhel70-3.4.7.tgz # rename the decompressed file mv mongodb-linux-x86_64-rhel70-3.4.7

Installing and uninstalling MongoDB 3.4 using the Yum source on CentOS 71. Configure the Yum sourceVim/etc/yum.repos.d/mongodb-org-3.4.repo[mongodb-org-3.4]Name=mongodb Repositorybaseurl=https://repo.mongodb.org/yum/redhat/$releasever/mo