SEARCH KEYWORD -- Distributed system


  Books for entry level C programmers

In computing, C is a general-purpose programming language initially developed by Dennis Ritchie between 1969 and 1973 at Bell Labs Its design provides constructs that map efficiently to typical machine instructions, and therefore it found lasting use in applications that had formerly been coded in assembly language, most notably system software like the Unix computer operating system.To learn C, we need to read many C books and have many practices. Here we summarize a list of C books which may h...

   C,Book,Beginning     2012-07-26 14:00:51

  Different module types in Java 9

Java 9 is going to introduce a disruptive change to the Java platform -- Module System. The module system will change how Java applications work in the future. It's like changing the foundation of a house without impacting the house functionality and its top level structure. This obviously is a big challenge for the whole Java community.  To bring as little pain as possible to migrate existing applications to Java 9 without refactoring the whole application, Java 9 will introduce a few diff...

   JAVA,JAVA 9,JIGSAW,MODULE SYSTEM,UNNAMED MODULE,AUTOMATIC MODULE,NAMED MODULE     2016-04-15 07:15:23

  My frequently used Linux commands

In our day to day work. We may have many chances working on Linux/Unix systems. There are many things we may need to do, checking logs, navigating in directories, creating file or installing software. We may use many commands to complete the work, such as ls, mkdir, cd etc. Below are my frequently used Linux commands or programs recently: pwd : print working directory, sometimes I need to check which working directory I am in in order to know where to go next. ls : List current directory files,...

   Linux,Command,Program     2012-08-16 15:09:42

  Want to be a Java developer?

Java is one of the top 3 programming languages in the world. It can be used to develop both web applications and desktop applications and more importantly it is cross platform--write once, run everywhere. Also, it's easy to pick up. If you want to be a Java developer, please get to ask yourself whether you know below listed topics. This list is summarized by Vivek Vermani, a Senior Java Developer: For a Core Java Developer , Ffollowing topics should be good. OOPs Concepts Abstract Classes and I...

   Java,developer,resource     2014-06-19 06:18:47

  Find files by size in Linux

In Linux systems, you may encounter a situation where there is no enough space on the system while you are trying to install some new packages or writing some data. In this case, you may want to clear some unneeded files. A frequent need will be find the largest files in the system so that they can be deleted first and disk space can be released quickly. In this post, we will show a simple command to find files by size so that we know what files are taking the specified space on the system, This...

   LINUX,FILESIZE,FIND     2020-04-25 08:02:45

  Set up Superset on ubuntu 16.04 LTS

Apache Superset (incubating) is a modern, enterprise-ready business intelligence web application. Compared with business-focused BI tool like Tableau, superset is more technology-navy. It supports more types of visualization and able to work in distributed manner to boost the query performance. Most importantly, it is free of charge! An example dashboard: Let’s go and set it up. Create a virtualenv Assume Anaconda is installed for python management. # create a virtualenv with python 3.6 co...

   TUTORIAL,UBUNTU,SUPERSET     2019-10-19 21:34:55

  ByteBuffer in Java

ByteBuffer is introduced in java.nio since Java 1.4. It provides a way of representing raw structured data such as from a file or from network. It enables fast access of underlying data compared to traditional ways like byte[] Prior to Java 1.4, if you want to represent a structured raw data, you need to create a byte[] and then having a set of checks to delimit the byte array to get the expected tokens. There are three ways to create a ByteBuffer: Wrapping an exiting array by calling ByteBuffe...

   JAVA,BYTEBUFFER,ALLOCATION     2015-07-08 03:17:44

  Set file permission in Java

Prior to Java 6,  there is no good solution at the Java level to provide file permission management. You need to implement your own native methods or call the Runtime.exec() to invoke the system routine such as chmod in LInux. Since Java 6, Java introduces a set of methods which can be used to set the file permission at Java level. These methods include: File.setReadable(boolean); File.setWritable(boolean); FIle.setExecutable(boolean); File.setReadable(boolean, boolean); File.setWritable(bo...

   JAVA, FILE PERMISSION, POSIX,learnjava     2015-08-29 03:37:37

  Microsoft to lay off Zune

Recently we can see many news about Microsoft's Windows 8, Microsoft puts much effort to promote Windows 8.  A few days ago, Microsoft announced the death of Windows Live brand, instead they will integrate it into the Windows system. Also, Microsoft now plans to lay off its Zune and focus on XBox, let XBox be the main entertainment service of Microsoft. XBox can provide  music and videos, it can also let users play video games.Here is a part of Microsoft's announcement:This year, Xbox ...

   Windows 8,Zune,XBox,Microsoft,Layoff     2012-05-30 08:14:58

  How Query Optimizer Works in RDBMS

In a previous post, we discussed how the various relational operators are implemented in relational database systems. If you have read that post, you probably still remember that there are a few alternative implementations for every operator. Thus, how should RDBMS determine which algorithm (or implementation) to use? Obviously, to optimize the performance for any query, RDBMS has to select the correct the algorithm based on the query. It would not be desirable to always use the same algori...

   DATABASE,DATABASE DESIGN,DATABASE OPTIMIZATION     2019-04-20 07:26:32

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