Difference between Linux and Unix LINUX Cost : Linux can be freely distributed, downloaded freely distributed from magazines, books etc. Developed : Linux Kernel is developed by the community. Linux Torvalds oversees things. Price : Free but support is available for a price. Security : Linux has about 60-100 Viruses listed till date. None of them activity spreading nowadays. Architectures : Originally developed for Intel x86 hardware, ports available for over two dozens CPU types including ARM. Examples : Ubuntu Fedora red hat, debia, Android etc. Processor : Dozens of different kinds. UNIX Cost : Different flavors have different cost. Developed : Three biggest distributions are Solaris , IBM and HPUX. Price : some free development use but support is available for a price. Se curity : A rough estimate of Unix virus is between 85 - 120 viruses reported till date. Examples : OS X, Solaris, all Linux Processes : x86/x64, spar,...
Aggregation and Functional dependency in DBMS Aggregation In aggregation the relation between two entities is treated as a single entity. In aggregation relationship with its corresponding entity is aggregated into higher level entity . It is the process of compiling information on object, there by obstructing a higher level. On limitation of the ER model is that it can not Express relationship among relationships. The aggregation represent a relationship between a whole object and its component in other word we can say that using aggregation we can express relationship main relationships. For example center entity offer the course entity act as a single entity in the relationship which is in a relationship with another entity visitor. In the real world if a visitor visits a coaching center they will never inquiry about the course or just about the center instead he will ask the inquiry about both. Functional dependency Functional dependency play an ...