Today's Question:  What does your personal desk look like?        GIVE A SHOUT

SEARCH KEYWORD -- System admin

  20 Database Design Best Practices

Use well defined and consistent names for tables and columns (e.g. School, StudentCourse, CourseID ...).Use singular for table names (i.e. use StudentCourse instead of StudentCourses). Table represents a collection of entities, there is no need for plural names.Don’t use spaces for table names. Otherwise you will have to use ‘{‘, ‘[‘, ‘“’ etc. characters to define tables (i.e. for accesing table Student Course you'll write “Student Cour...

   Database design,20 tips,Well defined name,Design pattern     2012-02-07 12:10:48

  Create cron job on CentOS

These two days, I am building a website and deploying it on a VPS server which uses CentOS 5. I don't have cPanel or Plesk for my account, so I need to install and configure everything myself including Apache, PHP, MySQL and FTP server, also today's topic cron job. Since my website has a ranking algorithm to calculate the rankings of each link and update the ranking on database and I need to calculate the rankings every 5 minutes, so I think to use cron jobs. Here are what I have done which may ...

   cron job,crontab,CentOS,linux,php,example     2012-06-11 09:23:45

  Eclipse 4.4 is going to fully support Java 8

Eclipse is the most popular IDE for developing Java applications, but it seems lag behind the Java 8 release a couple of months ago. The current Eclipse is not supporting Java 8 and if you want to run Java 8 programs on it, you need to install a plugin. You can find the plugin at the Eclipse market place. Now Eclipse 4.4 is coming to us on 25th June and the code name for it is Luna. This new version of Eclipse introduces some new features which can ease developer's work, these features includin...

   Eclipse,Luna,Java 8     2014-06-18 05:00:37

  The difference between System.load and System.loadLibrary in Java

When writing code using native library in Java, normally the first step is loading some native library. static{ 　　System.load("D:" + File.separator + "Hello.dll"); } JDK provides two ways to load libraries: System.load(String filename) System.loadLibrary(String libname) This post will try to explain the differences of these two ways. According to Java Doc on System.load(), it has below description. Loads the native library specified by the filename argument. The filename a...

   NATIVE,JNI,JAVA,SYSTEM.LOAD,SYSTEM.LOADLIBRARY     2019-02-05 05:49:28

  Lots of Chinese users experienced Samsung phone crashes

Starting from 23 May morning(Beijing time), lots of Samsung phone users in China suddenly experienced system crashes and couldn't use the phone anymore.   The symptoms the users saw were that the phone started to restart infinitely and the screen turned into dark screen and nothing can be done to get it recovered. Based on the reports, the impacted models include Samsung Galaxy S8, S9, S10 and S20 series,  Other models don't receive many reports yet. After receiving the reports,...

   SAMSUNG,SAMSUNG GALAXY,SYSTEM CRASH,AUTO UPDATE,NEWS     2020-05-23 05:23:55

  Networking Terminologies

Portmaps sudo apt-get install -y portmap Portmap is a part of ONC RPC (Open Network Computing Remote Procedure) collection of software for implementing remote procedure calls between Computer Programs. It is widely used by NFS (Network File System) and NIS. Portmap is a server that converts RPC program number to DARPA protocol port number. It must be used in order to make RPC calls. Network Infomation Service (NIS) sudo apt-get install -y nis NIS is a client server directory service provi...

   Linux,Network programming,Network file system     2012-02-16 06:22:30

  Using public key authentication in SSH

SSH is a popular cryptographic network protocol for secure network service operation. It is frequently used in remote server login. For a system administrator or software developer, SSH is frequently used to access remote servers or development servers or testing servers etc.  To login with SSH, there are different authentication mechanisms : password, public key and interactive etc. If a remote server needs to be accessed frequently, password authentication may be too troublesome as p...

   LINUX,DEBUG,SSH,PUBLIC KEY     2016-09-10 05:55:46

  Update & Delete Kubernetes resources in one-line command

It recently troubles me that my GKE cluster is managing more and more resources and causing difficulties in maintenance, one of which involves how to delete resources properly. Next, I will explain step by step the difficulties I encountered in my work and how I finally used the combination of bash commands and kubectl to implement the edition of Kubernetes objects through one-line command. In general The following are the basic operations that almost every Kubernetes user takes. Check ðŸ‘â€...

   KUBERNETES     2020-11-01 04:16:47

  3 ways to remove duplicates in List

Frequently, we may have an ArrayList which stores many values, and we need to process the ArrayList and get what are the distinct values in the list, or we may want to count occurrence of each value in the ArrayList. We can remove the duplicates in a few ways. Here we propose 3 methods :     public static void main(String[] args){        //SuperClass sub=new SubClass();                String[...

   Java,List,Duplicate,Clear     2012-09-03 09:44:32

  Shortest command on Linux

Usually when we log in to a Linux system,. we may type some frequently used Linux commands such as pwd,ls, ps etc. All these commands are really simple but powerful with different options. But do you know what is the shortest command on Linux? The answer is w. According to Linux manual, w will show who is logged on and what they are doing on the system. w displays information about the users currently on the machine, and their processes. The header shows, in this order, the current time, how l...

   Linux,w,shortest command     2014-04-30 11:07:38

RECENT