Re: Entity data spread over multiple tables

From: --CELKO-- <joe.celko_at_northface.edu>
Date: 25 Jan 2004 19:40:24 -0800
Message-ID: <a264e7ea.0401251940.7610eae3_at_posting.google.com>


>> with the downside that PHONE is a separate table, and I have to
access a second table to collect all info for a single PARTICIPANT. <<

Wrong model; the unit of work is the entire **schema**, not tables. Tables are sets; you are getting the data for the **entire set of participants**, not to a single participant.

>> This rubs me a little funny because I would model this differently
in a programming language like Java. <<

Try writting the code to do a relational division in Java -- about 100 lines of code. Columns are not fields; rows are not records; tables are not files. The table is the only data structure in SQL -- no arrays, linked lists, records, etc.

>> do other people hit this type of modeling problem often? <<

Sure! And when you learn LISP, the only data structure is a linked list. When you learn ICON, the only data structure is a string. You need to shift your mental model. Received on Mon Jan 26 2004 - 04:40:24 CET

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