Re: Multiplicity, Change and MV

From: Neo <>
Date: 13 Apr 2006 14:30:50 -0700
Message-ID: <>

> I don't know your definition of schema.
> I have searched Codd's 1970 ACM paper and found 0 occurences of this word.

Hmm. Interesting. My engineering background may have influenced my terminology. With respect to RMDBs, I use the term schema to mean the overall db structure that allows one to store data for a particular application. The main components of the structure being tables, fields, field types and the relationship between keys. When printed out from SQL Server or Access on a size E sheet via a plotter, some of my past projects displayed as many as 50 or 60 vertical rectangular blocks, the top of each labeled with the table name, listed within the box are the field names and crisscrossing lines connect the primary/foreign keys of various tables. Little icons on the diagonal lines indicate the relationship type (one-to-one, one-to-many). This sheet gets spreadout on the conference table at various meeting through out the project's life so that all the developers are on the same track. It the large sheet that typically hung behind me from the top of the cubicle divider to the floor and ended up with bloody marks from various color markers as the project progresses. If there is a more appropriate term, please advise. Received on Thu Apr 13 2006 - 23:30:50 CEST

Original text of this message