Member Avatar for axxouk

imaginary language into java. I have everything down except for the symbol table.

I am currently making ERD diagram for a library . The entities are below:

Entity Attributes
Member memId, memName, memAddress, memMaxbooks

Book isbn, bName, datePublished, pubId*, ageLower ageUpper, value

Copy cId, isbn*, dateAcquired, dateDestroyed

Loan memId*, memId*, dateOut, dateDue, dateBack

Publisher pubId, pubName, pubAddress

Author authorId, authorName

Authorship authorId*, isbn*

My ERD diagram is half finished and attached to this thread so please please please help me

ERD_DIAGRAM).doc (34.5 KB)
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  • Latest Post Latest Post by al3amer
Member Avatar for timothybard

I reviewed the document you attached; however, do you have any questions that you need answered? You mention that your ERD is half finished; are you unable to finish it and what do you need help with?

I see you have author, publisher and authorship listed as entities, but you don't have them in your diagram. Is that what you need help with? Do you need help with the loan entity? The loan entity would simply be located where the 'borrows' relationship is. Also, I believe the second Fk in the loan entity should be cID and not memID.

Member Avatar for al3amer

hello

why u 're writing these attributes in loan entity:memId*, memId*, dateOut, dateDue, dateBack!!!!??

the relationship is that a Member will loan a Book
so the relationship N:M between,so u have to write the loan as an entity with both pk of the member and book as fk and the most important attributes which is included in loan relationship

so the loan entity will inculde:memId,isbn,dateOut, dateDue, dateBack...

Edited by al3amer because: n/a
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