Here is a situation where storing some information in a database might be useful. Read the description, and then do the entity-relationship modelling, see below. Once upon a time, in the tiny village of Hatley, there was a library, where people could borow books. It worked like this: 1. You found a book on the shelves. 2. You took it to the Librarian, sitting at an ornate desk crafted by Jean, an excellent local woodworker. 3. The librarian took a card out of the book (or made a new card if necessary), stamped the date due on it and a slip at the back of the book, then put the card in a pocket with your name on it (unless you already had 3 unreturned books) 4. If you returned a book, this process was basically undone. Books need to be identified by title, possibly year, and author. (In case of multiple authors, this attribute can hold the first author, or both, for example, 'Kernighan & Ritchie'). As the "computer guy" I was asked to "put all this on the computer" (A Bishop's discard.) I declined. Today, I might do it, using database software. (The larger village of North Hatley now uses a computer for this.)

Here is a situation where storing some information in a database might be useful. Read the description, and then do the entity-relationship modelling, see below. Once upon a time, in the tiny village of Hatley, there was a library, where people could borow books. It worked like this: 1. You found a book on the shelves. 2. You took it to the Librarian, sitting at an ornate desk crafted by Jean, an excellent local woodworker. 3. The librarian took a card out of the book (or made a new card if necessary), stamped the date due on it and a slip at the back of the book, then put the card in a pocket with your name on it (unless you already had 3 unreturned books) 4. If you returned a book, this process was basically undone. Books need to be identified by title, possibly year, and author. (In case of multiple authors, this attribute can hold the first author, or both, for example, 'Kernighan & Ritchie'). As the "computer guy" I was asked to "put all this on the computer" (A Bishop's discard.) I declined. Today, I might do it, using database software. (The larger village of North Hatley now uses a computer for this.)

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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