Design by ER-Diagram :

ERD 1: The Olympic facilities are divided into sports complexes. Sports complexes are divided into onesport and multisport types. Multisport complexes have areas of the complex designated for each sport with a location indicator (e.g., center, North East corner, south, etc.). A complex has a location, chief organizing individual, total occupied area, and so on. Each complex holds a series of events (e.g., the track stadium may hold many different races). For each event there is a planned date, duration, number of participants, number of officials, and so on. A list of all officials will be maintained together with the list of events each official will be involved in. Different equipment is needed for the events (e.g., goal posts, poles, parallel bars) as well as, another set of equipment is needed for the maintenance of each sports complex (e.g. cleaning equipment, grass cutters, etc.). The two types of facilities (one-sport and multisport) will have different types of information. For each type of facility, there are number of amenities available (e.g. internet caf, gym, pool, etc.) together with an approximate budget for each amenity.

ERD 2: Consider an online auction database system in which members (buyers and sellers) participate in the sale of items. The data requirements for this system are summarized as follows: - The online site has members who are identified by a unique member id and are described by an email address, their name, a password, their home address, and a phone number. - A memb er m ay b e a b u yer o r a s ell er. A bu yer h as a s hipp in g ad d r ess r eco rd ed in th e d at ab as e. A s el ler h as a b an k acco u nt n um b er an d routing number recorded in the database. - Items are placed by a seller for sale and are identified by a unique item number assigned by the system. Items are also described by an item title, an item description, a starting bid price, bidding increment, the start date of the auction, and the end date of the auction. - It em s ar e al so cat ego r iz ed b as ed o n a f ix e d cl a s s if i cati on hi e r ar c h y ( f o r ex ampl e a m od em m a y b e cl a s s i fi ed as com put er/ h ar dw ar e/ m od em ) . - Buyers make bids for items they are interested in. A bidding price and t i m e o f b i d p l a c e m e n t i s r e c o r d e d . T h e p e r s o n a t t h e e n d o f t h e a u c t i o n w i t h t h e h i g h e s t b i d p r i c e i s d e c l a r e d t h e w i n n e r a n d a t ransaction between the buyer and the seller may proceed soon after. - Buyers and sellers may place feedback ratings on the purchase or sale of a n i t e m . T h e f e e d b a c k c o n t a i n s a r a t i n g b e t w e e n 1 a n d 1 0 a n d a comment. Note that the ratings are placed on a completed transaction by the buyer or seller of the item in the transaction.

ERD 3: The data requirements of the library application are summarized as follows: BOOK entity is identified by BookId, it has title and multiple author names. PUBLISHER entity consists of Name, Address, and Phone attributes publisher may have many phone numbers. Name is the key for the PUBLISHER. LIBRARY_BRANCH entity has BranchId as a key and Branchname attribute additionally. BORROWER entity has BrowerId as key and additionally has name, address, phone attributes. Each LIBRARY_BRANCH has one or more copies of the same book. In such a case, noOfCopies attribute needs to be maintained by the relationship. A book is published by only one publisher. A book can be loaned to a borrower at a specific library branch.

Note: Please draw it in an understandable way, in excellent handwriting