more info on help with mapping
Sorry didnt mean to be cheeky just got confused and wanted some advice to make sure i have got the right erd and your questions have really helped. Actually thought i was doing ok but dont have any teachers to go to as i am doing self study. Now that i know that mapping means getting the right tables, columns, primary key, foreign keys and indexes(what do you mean by indexes know the rest but dont understand indexes?) once i get the erd right i should be able to do it my self
I am trying to create a loans information system from an exercise i am doing (trying to learn oracle as you can see i a not that good hence the stupid questions).
The company offers commercial loans and equity loans to its clients. Applicants for the loans can be single or private individuals, married couples or business organisations. The commercial loans can be secured with collateral in the form of insurance, property, stock or any bonds accepted by the company. The company has three branches London,Newyork and Johannesburg. London and Newyork are the operational branches and the hq in jburg only houses the manage staff. both the operational branches will utilise identical schemas in terms of the database system.
The subtyping for client was used because the clients applying for loans will fall under 4 different categories as shown in the erd (single/private/married/business org.
In terms of setting the attributes if i change the attibutes to the following would it help:
First name/last name changed to client name
salary change to income
dob removed
gender removed
or should i have different attributes for the different subtypes and just leave the primary key under client as the only attribute.
There is a client category as an attribute and i was going to use a check constraint to select all the different attributes.
In terms of the branch entity i have used the sub type because i am going to be distributing the loans systems as follows:
1 the commercial loans data will be stored at the london site
the home equity loan at the newyork site.
I was going to fragment it by creating a view to select all the commercial loan data where the location is for london (am i right in using subtypes and should the branched have different attributes).
Now that you know about the business can you give me advice on where i can improve my ERD.
1 Attachment(s)
new schema with attachment
I have made some changes to the schema based on the advice i recieved and would like to know if i am on the right track. I dont know if i have got the right name for the entity loan_type_location any suggestions will be greatly appreciated