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Some notes related to Linux and Programming

Java - static Keyword

static In simple words: static means the variable or methods that assigned to are belonging to the class, not the object. Therefore, there鈥檚 only one copy of the variable/method in the memory. When create an object where all instance variables aren鈥檛 static, every object will own its memory space, and its own copy of value. Suppose we have a ball class: class Ball{ double radius; final double PI = 3....

April 18, 2022 路 5 min 路 Derry

Keys in Database

There are 8 types of keys in DBMS(Database Management system). Keys are used to help developers to identify a row in a relation(table). Understanding each keys will help you understand and develop a database. In modern world, data is growing at a rapid pace. So does the demand for professional data analyst. In this article, I will help you understand the keys in DBMS. I suggest you have memorize these terms as it will help you build a logical database and if later on you want to expand the program, you don鈥檛 have to start over....

March 17, 2022 路 4 min 路 Derry

How to Format Flash Drive

How to format USB (flash drive) in Linux command line? Flash drives are very commonly used. From time to time, we stored our files, presentations, logs in this drives. It鈥檚 a convenient way to copy and carry around. Sometimes, we鈥檒l like to reformat a flash drive, either to use a different file system or to clean up for friend. In Linux, there are several graphic software that provides you the same ability....

March 17, 2022 路 5 min 路 Derry