ITEC 3030 Lecture Notes - Lecture 1: General Idea, Transaction Processing, Chen Model
Document Summary
In two phase commitment of acidity fails administrator must intervene. Other transaction protocol is that it allows for immediate update of the transaction without waiting, if something wrong happens, reverse updates are performed. It is a approach to entity modeling which still used widely for representing conceptual schemas of databases. |= ( three ) means one or more. Cust number, name, bill address etc. ( all in one box ) The class diagram is a unified modeling language. Domain class diagram: models things in the users work domain, it is representation of reality the domain which has nothing to do with programming classes, contains only attributes. Design-level class diagram: models software classes, adds method as behavior, used in design activity, more relevant to ad. Design class diagram in in analysis phase of sdlc, and domain diagram is in design phase, then ad sits between analysis and design as it mentioned before.