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Insertion sort The basic operation of insertion sorting is to insert a record into an ordered table that has been sorted, so as to get a new ordered table with the number of records increasing by 1. The sorting process is roughly as follows: Starting with the first element, the element can be considered sorted. Remove the nex ...

After "$" corresponds to the Shell command of Linux, and after "hive >" corresponds to the command in CLI. CLI options - help to see the parameters of hive $hive --help --service cli usage: hive -d,--define <key=value> Variable subsitution to apply to hive commands. ...

The ps command in Linux is the abbreviation of Process Status. The ps command lists the processes currently running in the system. The ps command lists snapshots of the current processes, which are those processes at the time of execution of the ps command. If you want to dynamically display process information, you can use the top command. T ...

The Kill Command in Linux is used to terminate the operation of a specified process. It is a common command for process management in Linux. Usually, the Ctrl+C key can be used to terminate a foreground process, but for a background process, we need to terminate with kill command. We need to use tools such as ps/pidof/pstree/top to get the pro ...

When processing matched files with the - exec option of the find command, the find command passes all matched files together to exec for execution. But some systems limit the length of commands that can be passed to exec, so that overflow errors occur after the find command runs for a few minutes. Error messages are usually "parameter col ...

Two days ago, I asked my classmates to help me become a king. He needed heroes, but I didn't have gold coins. I couldn't afford them. (How important is money!!) I have to brush gold coins in the clouds, but I'm so lazy that I don't want to brush them manually. So, try to do something about it. After a long battle (as if it wasn't too long), it ...

brief introduction MVC is a design pattern, that is, a method and idea to solve problems, which was put forward in the 1980s, and has a long history. The significance of MVC is to guide developers to decouple data from presentation and improve the reusability of code, especially part of model code. MVC mode means that software can be divided ...

Abstract MongoDB3.x is quite different from previous versions. Here's a brief introduction to user authentication. 1. Understand the 3.x version of the add user function Function: db.createUser(user,writeConcern); Parameters: User This document is about user identity authentication and access related information; Write Concer ...

Simple definition: public key and private key. Encryption and decryption use two different keys, so they are asymmetric. System: ubuntu 14.04 Software: openssl java php   Generating public key and private key Use commands to generate private keys: openssl genrsa -out rsa_private_key.pem 1024 Parameter: genrsa generated key - out output to fi ...

Not long ago, interns, now in the group to help dalao s run Case, from time to time to collect a wood Dump, every time the command is too annoying, so forced to learn to write their own Shell scripts. It was really painful at first, and I couldn't get any books. I could only draw pictures with half-truthful and half-truthful information on the ...