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Work-in

Solution for the Quiz –Problem 1. DID. names. salary. names. EID. Can be Pkey. Work-in. emp. dept. manage. DID. quantity. ID. description. names. names. carries. item. dept. names. address. price. SID. supply. supplier. quantity. Ship addr. id. ID. description. date.

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Work-in

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  1. Solution for the Quiz –Problem 1 DID names salary names EID Can be Pkey Work-in emp dept manage

  2. DID quantity ID description names names carries item dept names address price SID supply supplier

  3. quantity Ship addr id ID description date name Order-detail item order Can be empty ? • Each manager’s salary is higher than all other employees in the dept he/she manages • Each item must be at least supplied by three suppliers

  4. Multiplicity • Comes from UML. Some ER or EER apply this notation. • One constraint which is specified in the form (min,max) to specify the limit on participation. • Each item must be supplied from at least three suppliers ---(3,*) • the total participation => (1,*) • The partial participation=>(0,*) • Key constraint=>(0,1) • Can we combine the above to express (3,*)?

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