Generalization/Specialization?
From: John <google_at_tsn.cc>
Date: 23 Oct 2002 08:15:32 -0700
Message-ID: <b43220c6.0210230715.6ce775a8_at_posting.google.com>
Hello,
I am new to database modelling and was wondering if any of you could help me.
I have a description of what the database should support and so have to figure out the entities and relationships myself. It is of a medical clinic. Now the clinic has "supplies" of "surgical" and "non-surgical" items. From the description, both surgical and non-surgical supplies have exactly the same attributes, with itemNo the primary key. There is also another supply the medical clinic holds and that is "pharmaceuticals". This has a few attributes the same such as reorder Level, quantity and cost but the primary key is drugNo. SO the surgical and non-surgical supplies each hold the same attributes including itemNo as both their primary keys and pharmaceutical supplies holds a few attributes that are the same as the surgical and nonsurgical but has drugNo as the PK. SHould I combine surgical and nonsurgical with simply and attribute that tells whether nonsurgical or surgical.
So i would have:
clinic - supplies (itemNo,....reorder Level, flag (tell whether s or ns)etc)
Date: 23 Oct 2002 08:15:32 -0700
Message-ID: <b43220c6.0210230715.6ce775a8_at_posting.google.com>
Hello,
I am new to database modelling and was wondering if any of you could help me.
I have a description of what the database should support and so have to figure out the entities and relationships myself. It is of a medical clinic. Now the clinic has "supplies" of "surgical" and "non-surgical" items. From the description, both surgical and non-surgical supplies have exactly the same attributes, with itemNo the primary key. There is also another supply the medical clinic holds and that is "pharmaceuticals". This has a few attributes the same such as reorder Level, quantity and cost but the primary key is drugNo. SO the surgical and non-surgical supplies each hold the same attributes including itemNo as both their primary keys and pharmaceutical supplies holds a few attributes that are the same as the surgical and nonsurgical but has drugNo as the PK. SHould I combine surgical and nonsurgical with simply and attribute that tells whether nonsurgical or surgical.
So i would have:
clinic - supplies (itemNo,....reorder Level, flag (tell whether s or ns)etc)
- pharmaceutical (drugNo....reorder Level etc)
How can I go about modelling this??
Any help would be greatly appreciated
Thankyou Received on Wed Oct 23 2002 - 17:15:32 CEST