E/R questions

From: Jay Krishnamurthy <jkrish_at_lpp.sdi.agate.net>
Date: 1997/05/15
Message-ID: <337B2D9B.6D04_at_lpp.sdi.agate.net>#1/1

[Quoted] [Quoted] I have an entity that contains zip code and city.

[Quoted] [Quoted] I would like to establish another entity called distance that contains "From zip", "To zip" and "distance". Any ideas on how to represent this in an Designer/2000 E/R diagram?

[Quoted] Should distance be a sub-type within zip, and have a recursive (pig's ear) relationship to itself? i.e.

   ZIP

---

| zip code |
| city |
| |
| -------------- |
| |distance | |
| ------------- |

   |-----------------------|

The sub-type has a recursive relationship to itself. Is this valid?

Or is there a better way to represent this?

Thanks. Received on Thu May 15 1997 - 00:00:00 CEST