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The commands in this article are all real-time under the mongo shell. In real web projects, the corresponding implementations of these commands are encapsulated, so there is no need to be scared. Put on the official orthodox documents first English document The links below are all from the Chinese community. There are many ways for ...

. tar Packing multiple files together and decompressing the packaged files - z # Compression or decompression via gzip - c # Create a new jar package - v # Displays the tar command execution process - f # Specify the file compression name - t View the contents of the compressed package without decompressing it __________ - p # Keep the ...

What is the 0x01 ls command? The system environment I use is Ubuntu 18.04, and the ls command tells us what files are in the current directory: The ls command also has common parameters: -l: List file details -a: List the files that contain the beginning of. -s: file size is printed in blocks -t: Sort output by tim ...

GAWK: Report Generator, Formatted Text Output 　　　　awk [options] 'program' var=value file... 　　　　awk [options] -f programfile var=value file... 　　　　awk [options] 'BEGIN{ action;... } pattern{ action;... } END{ action;... }' file ... The awk program component: BEGIN statement block, general statement block that can use pattern ...

Summary Because the Internet entrance traffic is mainly occupied by search engines, the ranking of websites in search engines directly affects the marketing effect, so the SEO service came into being at the historic moment. Search Engine Optimization (SEO) is called Search Engine Optimization (SEO). It refers to the use of search engine rules t ...

1. django-admin command Enter django-admin at the command prompt to view subcommands [django]  check  compilemessages   createcachetable  dbshell  diffsettings  dumpdata  flush  inspectdb  loaddata  makemessages  makemigrations  migrate  runserver  sendtestemail  shell  showmigrations  sqlflush  sqlmigrate  sqlsequencereset ...

Container is optional in yarn. This paper introduces the following two types: DefaultContainerExecutor  LinuxContainerExecutor  Controlled by configuration parameters: yarn.nodemanager.container-executor.class   When NodeManager initializes, load org.apache.hadoop.yarn.server.nodemanager.NodeManager#serviceInit     // ...

You can edit py files with vim in the shell, or you can write code with pycharm, with. py as the file name The simplest code presentation #!/usr/bin/env python # _*_ coding: utf-8 _*_ # @Time : 2017/3/13 10:15 # @Author : eason # @File : FirstProgram.py print("Hello World!") Meaning of variables: Store temporary data while the program ...

Heap sort 1. Introduction of Trees and Binary Trees A tree is a data structure such as a directory structure. Tree is a data structure that can be defined recursively A tree is a set of n nodes: If n=0, then this is an empty tree. If n > 0, there is one node as the root node of the tree, and the other nodes can be divided into m sets, eac ...

1. View disk space: Since it is a regular backup, we should choose a disk space with sufficient space to avoid the consequences of backup failure and data loss caused by insufficient space! __________ Storing on the current disk is the simplest, but it is the least recommended; servers have multiple hard disks, it is best to store backups o ...