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Friday, February 22, 2019

Database+Coursework Database 101

Area Film and Literary party (MLFS) provide groups and faces for topical anesthetic people. All participants must be elements (who pay an annual fee) or their guests who whitethorn attend events. Fees vary from one group to another. In addition members may gravel a reduction in fees depending on their eccentric of membership. For mannikin Individual members pay 100% fees and Concessionary members pay 50%. There atomic number 18 also Household members and a superfluous category called Friends of the Society. The Society hosts a number of groups which meet monthly. parts can join one or more(prenominal) groups currently these include Film, Science, Reading and Poetry companys. A paper eternalize is held for to each one member, an example of which is given below. Member details Event talents Member No1022 NameJay PatelTelephone020 8888 3333AddressHigh Rd, London Member type Individual Ability Code endowment 01 Poetry 05 Science membership records Session (year) Group code Group hang CoordNo CoordName Feepaid Date paid 2007-2008 01 Poetry 102 Carol Duffy ? 0 19/09/07 2008-2009 01 Poetry 102 Carol Duffy ? 60 02/09/08 2008-2009 06 Reading 111 Jane Austen ? 75 03/09/08 2009-2010 05 Science 181 Marie curie ? 90 03/09/09 * * * * * * * Note that the group code and the ability code argon both based on the same domain of values. The latter represents members talents which the Society may make use of this is described later. One group of a particular type (such as Poetry) forget be run each year, assuming there are nine or more members who require to join a group.Each group is run by a coordinator, who may change from one year to the next. In addition to the above, the society holds the manage and telephone number of each coordinator. Besides groups, the society also holds one-off special events, such as lectures, films, art exhibitions and melodyal evenings. Events do not affect to particular groups they are open to all members and t heir guests and are organised by one of the coordinators. Events will be led by an outside turn toer, or sometimes a member (who have special talents as shown in the example record above) will act as the speaker.Each event will have only one speaker (whether an outside speaker or a member speaker), but a speaker may speak at a number of events. Details will be held of the event name, the date, and venue and outside speakers (name and telephone number). The Society will keep records of members who accompanied events and the number of guests for each member per event. 1a) Entity- traffichip model mapped to a relational database If you take up to revise this topic, see Text Book Chapter 3. Produce an Entity-Relationship Model using UML notation for the above case.Convert to a relational model by specifying the immemorial and foreign keys, mapping any one-to-one relationships into relations, and decomposing any many-to-many relationships. This is the Relation plot and the diagram which you should submit. Note that there is no need to include the type of each attribute. State any assumptions that you may need to make especially about optional and mandatory relationships. Note that assumptions are about how you have interpreted the scenario, not about the E-R modelling process. The ERD is not trivial it involves at least 10 entities.I suggest you start by each member of your group concentrating on different parts of the ERD and then coming in concert to discuss. Remember * databases hold historical information, not just details of current records * to work out cardinality of relationship use two sentences each commencement with the word one * get wind all attributes they should be atomic (single-valued) * check primary/foreign key links (remember the foreign key goes on the many side) * decompose any mn relationships 1b) authorise the model Checking for connection boundsExamine your model and identify one potential trap (fan trap or chasm trap) if presen t. Consider whether this may cause a conundrum to your model and re-draw if necessary, arguing your case either way. Supporting the functional essentials sustain the model to check it can support the following functional requirement i. e. specify the access path by listing the appropriate relations (taking into account the correct relationships) from your diagram List all members by name who have ever belonged to the Science group, who have a talent for music and have attended an event with Goldie as the outside speaker.

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