TweetFollow Us on Twitter

May 91 Letters
Volume Number:7
Issue Number:5
Column Tag:Letters

HyperCard Letters

By Kirk Chase, Editor

Databases views

Paul Whittington

Vice-President

Griffin Software, Inc.

1790 Vermont Dr., Elk Grove, Illinois 60007

708/ 893-7238

I was astonished to learn from Mr. Joseph Terry, Jr. that the first “real” database has just arrived in the Mac world. I think Oracle Corporation also must be surprised to hear that they do not have a “real” database.

Mr. Terry writes, “Remember that those old guys and gals really DID know something.” As one of those old guys with over 15 years of experience in data processing (that shows you how old I am - I still refer to it as data processing), I have had experience with databases from mainframes to micros.

In both his letter in the January, 1991 issue of MacTutor and his article in the February, 1991 issue, Mr. Terry expresses his opinion that a network database model is the best type of database for “serious” database systems. I think that a more enlightened opinion is that each database model has its strengths and weaknesses, and that a database’s appropriateness is dependent on the application employing it.

In a hierarchical database, data is linked from parent to child with the constraint that each child can have only one parent. The limitation is that you can only arbitrarily traverse the database from top to bottom. This works well when all of your data has a one to many relationship and has very few levels in the hierarchy. For example, an order system might have an order header with name and address information. Each order header can then point down to a line item for that order. This causes no problems because the line item is meaningless without the order header.

Hierarchical databases have been around since the late sixties. Network databases became popular after the Data Base Task Group of the Conference on Data Systems Languages (CODASYL-DBTG) issued a report defining a data management system that supports a complete network structure (April 1971). Since Mr. Terry did a thorough job explaining the network database structure, I won’t repeat that here. The big advantage that a network database has over a hierarchical one is that a child record can have more than one parent record and that you can go up and down between children and parents to your heart’s content. The disadvantage is that it is real easy to get lost in the database if you are not careful.

The relational database model is based on research done by E.F. Codd. The model is based on the mathematical foundation of relational algebra, which gets into relations, domains, degrees, and tuples. A more easily understood description defines a relation as a table with columns representing fields and rows representing records. Many of today’s popular databases are built on the relational foundation. The strength of a relational database is in its ability to extract and combine data in many flexible ways. Its disadvantage has always been the processing overhead that it imposes.

The best use of a relational database is in situations where you cannot anticipate the end-user’s needs. A database with sales information is a great example of the need for a relational database. Marketing people love to aggregate data by weird demographic information.

Furthermore, no database product conforms exclusively to any one model. Even Mr. Terry refers to his product as a network database with relational extensions. Every database product on the market has “extensions” to take advantage of features from another model.

I think that when we talk about “serious” databases, we are talking multi-user, client-server stuff. Mr. Terry should look at the Database Access Manager for System 7. This is going to have a huge influence on how applications access databases. It also defines how a database server must look to its clients and, more specifically, how Macintosh databases must look to applications.

(And now a word from our sponsor.)

For the past two years Griffin Software has had two database engines for the Macintosh that use HyperCard as a front end. HyperHIT is based on the hierarchical database model with a few whiz-bang extensions thrown in. HyperHIT-R is based on the relational database model. Both are available now through our publisher, SoftStream International, Inc. Currently in beta is the multi-user version which supports both HyperHIT and HyperHIT-R files. The expected release date for HyperHIT-N is the month of April.

Both HyperHIT and HyperHIT-R were designed with HyperCard in mind. They don’t have fixed length fields. They store data, except for sounds and pictures, as ASCII text, just as HyperCard does. HyperHIT-R allows for dynamic modifications of the database structure, without using separate utility programs (importData and exportData are two of the XCMDs). HyperHIT-R also allows for those bizarre queries that those marketing people think up. (Can you tell which users give me the most sleepless nights?) Such as, “all of the people in Illinois, Indiana and Iowa who have purchased the book DRUG USE IN THE WORKPLACE but have not purchased the book BODY FLUIDS”.

We would appreciate the opportunity to present an article showing our products’ strengths, as you have afforded to Mr. Terry.

[You are perfectly welcomed and urged to submit an article on your product. In today’s world, even small products must be strong to compete. Many people have turned to different aids to help them get more “bang for the buck”. Products like yours, Mr. Terry’s, MacApp, etc. are all out there for developers to use. Only desperate developers, though, purchase products they know little about, they do so in hopes the products will aid their effort. It is therefore imperative to have products reviewed and advertised.-ed]

Listing Correction

Kirk Chase

MacTutor

The header file “CRemoveLFApp.h” was inadvertently left out of Wade Maxfield’s article, “Designing With Objects” in the January 1991 MacTutor. Below is the listing.

/* 1 */

/*****
 * CRemoveLFApp.h
 *
 * Application class for a typical application.
 *
 *****/

#define _H_CRemoveLFApp   /* Include this file only once */
#include <CApplication.h>

struct CRemoveLFApp : CApplication 
 {
 /* No instance variables */

 void IRemoveLFApp(void);
 void SetUpFileParameters(void);
 void DoCommand(long theCommand);
 void Exit(void);
 void CreateDocument(void);
 void OpenDocument(SFReply *macSFReply);
 void Run(void); /* override of built in method */
};

Strip Style FKEY

Thomas Nielsen

Vacaville, CA

Lately, I’ve found myself repeatedly frustrated by the simple operation of copying and pasting text in HyperCard 2.0. The problem occurs when I go to paste the text. It seems that HyperCard (many other applications) now copy the style of the text as well as the text itself. This is great until you have to go to the different menus to set the font, size, and style. Here is the code for a short little FKEY that strips away the style from the scrap, leaving only text.

/* 2 */

Handle NewClearSysHandle(long size){
 asm{
 move.l size,d0
 NewHandleCLEAR+SYS
 move.l a0,d0
 }
 }
 
void main(void){
 long scrapsize, offset;
 Handle h;
 
 scrapsize=0L;
 h=0L;
 if (!(h=NewClearSysHandle(0)))
 goto returnpoint;
 scrapsize=GetScrap(h,’TEXT’,&offset);
 if (scrapsize>0){ 
 SetHandleSize(h,scrapsize+(scrapsize &1)); /*make Handle even size*/
 ZeroScrap();
 PutScrap(scrapsize,’TEXT’,*h);
 SystemEdit(3); /*  Tricky part */
 }
returnpoint:
 if (h)
 DisposHandle(h);
 }

See the call to SystemEdit(3)? Well it took me FOREVER to figure that one out. The system won’t recognize that the scrap has changed until you do it. I hope I’m not the only programmer out there that’s had problems with this one!

For Think C project

 Project type->Code Resource
 Type:  FKEY (all capitols)
 ID:  7 (this is also the number key that invokes FKEY)
 Attrs:  20 (purgable)
 File Type:  rsrc (ResEdit)
 Creator:  RSED (ResEdit)
 Name:  Strip Style FKEY

[The full project and listing are included in this month’s source disk.-ed]

Multi-user AppleTalk For HyperCard

Kirk Chase

MacTutor

Epsi Computer Systems, Inc. has announced epsiTalk. This is a development tool for adding AppleTalk support for HyperCard 2.0. Using epsiTalk, you can incorporate distributive processing and file serving among network stations. This makes it ideal for work groups, conferencing, and multi-user applications. There are two versions, epsiTalk and epsiTalk-EZ selling for $175 and $395 respectively.

EpsiTalk has the ability of creating quick, distributive processing by allowing you to control other epsiTalk entities on other, idle Macintoshes. It comes equipped with tools for handling file transfers and access. EpsiTalk also supports aborting and clearing transmissions midstream.

For more information, contact Robert Eppich or Randy Young at

Epsi Computer Systems, Inc.

209-1255 56th Street

Delta, British Columbia V4L 2B9

Canada

(604) 943-8664

 
AAPL
$101.06
Apple Inc.
+0.10
MSFT
$47.06
Microsoft Corpora
-0.46
GOOG
$587.37
Google Inc.
-8.71

MacTech Search:
Community Search:

Software Updates via MacUpdate

Monosnap 2.2.2 - Versatile screenshot ut...
Monosnap allows you to save screenshots easily, conveniently, and quickly, sharing them with friends and colleagues at once. It's the ideal choice for anyone who is looking for a smart and fast... Read more
Tunnelblick 3.4beta36 - GUI for OpenVPN...
Tunnelblick is a free, open source graphic user interface for OpenVPN on OS X. It provides easy control of OpenVPN client and/or server connections. It comes as a ready-to-use application with all... Read more
SoftRAID 5.0.4 - High-quality RAID manag...
SoftRAID allows you to create and manage disk arrays to increase performance and reliability. SoftRAID's intuitive interface and powerful feature set makes this utility a must have for any Mac OS X... Read more
Audio Hijack Pro 2.11.3 - Record and enh...
Audio Hijack Pro drastically changes the way you use audio on your computer, giving you the freedom to listen to audio when you want and how you want. Record and enhance any audio with Audio Hijack... Read more
Airfoil 4.8.9 - Send audio from any app...
Airfoil allows you to send any audio to AirPort Express units, Apple TVs, and even other Macs and PCs, all in sync! It's your audio - everywhere. With Airfoil you can take audio from any... Read more
WhatRoute 1.13.0 - Geographically trace...
WhatRoute is designed to find the names of all the routers an IP packet passes through on its way from your Mac to a destination host. It also measures the round-trip time from your Mac to the... Read more
Chromium 37.0.2062.122 - Fast and stable...
Chromium is an open-source browser project that aims to build a safer, faster, and more stable way for all Internet users to experience the web. FreeSMUG-Free OpenSource Mac User Group build is... Read more
Attachment Tamer 3.1.14b9 - Take control...
Attachment Tamer gives you control over attachment handling in Apple Mail. It fixes the most annoying Apple Mail flaws, ensures compatibility with other email software, and allows you to set up how... Read more
Duplicate Annihilator 5.0 - Find and del...
Duplicate Annihilator takes on the time-consuming task of comparing the images in your iPhoto library using effective algorithms to make sure that no duplicate escapes. Duplicate Annihilator detects... Read more
jAlbum Pro 12.2 - Organize your digital...
jAlbum Pro has all the features you love in jAlbum, but comes with a commercial license. With jAlbum, you can create gorgeous custom photo galleries for the Web without writing a line of code!... Read more

Latest Forum Discussions

See All

This Week at 148Apps: September 15-19, 2...
Expert App Reviewers   So little time and so very many apps. What’s a poor iPhone/iPad lover to do? Fortunately, 148Apps is here to give you the rundown on the latest and greatest releases. And we even have a tremendous back catalog of reviews; just... | Read more »
Kitty Powers’ Matchmaker – Tips, Tricks,...
Hey There, Kittens: | Read more »
Goblin Sword Review
Goblin Sword Review By Andrew Fisher on September 22nd, 2014 Our Rating: :: RETRO GOODNESSUniversal App - Designed for iPhone and iPad Fun visuals, good music, engaging level design, and lots of content make Goblin Sword an... | Read more »
Major New Update for CSR Racing Adds Fer...
Major New Update for CSR Racing Adds Ferrari and Multiplaye​r Posted by Jessica Fisher on September 22nd, 2014 [ permalink ] | Read more »
Veditor Review
Veditor Review By Jennifer Allen on September 22nd, 2014 Our Rating: :: PIMP YOUR VIDEOUniversal App - Designed for iPhone and iPad Want to add stickers and music to your videos? Veditor can do that easily.   | Read more »
1849′s Nevada Silver DLC is Still Search...
A few months ago, I took a look at 1849 from SomaSim. This Gold Rush-themed city builder for iPad had a fair bit going for it, but lacked in a few crucial areas to make it a true stand-out on the App Store. SomaSim has since added in a sandbox mode... | Read more »
Fruit Ninja Will be Reborn With a Massiv...
Fruit Ninja Will be Reborn With a Massive Update and Origins Animation Series Posted by Jessica Fisher on September 22nd, 2014 [ permalink ] Halfbrick Studios is rebuilding | Read more »
Daniel Tiger’s Grr-ific Feelings Review
Daniel Tiger’s Grr-ific Feelings Review By Amy Solomon on September 22nd, 2014 Our Rating: iPad Only App - Designed for the iPad Daniel Tiger’s Grr-ific Feelings includes activities that allow young children explore different... | Read more »
CloudMagic Updated for iOS 8 – Adds Inte...
CloudMagic Updated for iOS 8 – Adds Interactive Notifications, Share Extension, and More Posted by Jessica Fisher on September 22nd, 2014 [ | Read more »
Starbase Annex (Games)
Starbase Annex 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: "it’s really very clever... a little bit of Hearthstone and a dash of Eclipse" - PocketTactics.com From the creator of Starbase... | Read more »

Price Scanner via MacPrices.net

Apple restocks some refurbished 2014 MacBook...
The Apple Store has restocked some Apple Certified Refurbished 2014 MacBook Airs, with prices starting at $769. An Apple one-year warranty is included with each MacBook, and shipping is free. These... Read more
13-inch 128GB MacBook Air on sale for $949, s...
B&H Photo has the new 2014 13″ 1.4GHz/128GB MacBook Air on sale for $949.99 including free shipping plus NY tax only. Their price is $50 off MSRP. B&H will also include free copies of... Read more
Apple offering free $25 iTunes Gift Card with...
The Apple Store is offering a free $25 iTunes Gift Card with the purchase of a $99 Apple TV for a limited time. Shipping is free. Read more
Apple refurbished iPod touch available for up...
The Apple Store has Apple Certified Refurbished 5th generation iPod touches available starting at $149. Apple’s one-year warranty is included with each model, and shipping is free. Most colors are... Read more
iFixIt Tears Down iPhone 6; Awards Respectabl...
iFixit notes that even the smaller 4.7″ iPhone 6 is a giant among iPhones; so big that Apple couldn’t fit it into the familiar iPhone form factor. In a welcome reversal of a recent trend to more or... Read more
Phone 6 Guide – Tips Book For Both iPhone 6...
iOS Guides has announced its latest eBook: iPhone 6 Guide. Brought to you by the expert team at iOS Guides, and written by best-selling technology author Tom Rudderham, iPhone 6 Guide is packed with... Read more
How to Upgrade iPhone iPad to iOS 8 without D...
PhoneClean, a iPhone cleaner utility offered by iMobie Inc., reveals a solution for upgrading iPhone and iPad to iOS 8 without deleting photos, apps, the new U2 album or anything. Thanks to more than... Read more
Inpaint 6 – Photo Retouching Tool Gets Faster...
TeoreX has announced Inpaint 6, a simple retouching tool for end users that helps remove scratches, watermarks, and timestamps as well as more complex objects like strangers, unwanted elements and... Read more
Worldwide PC Monitor Market Sees Growth in To...
Worldwide PC monitor shipments totaled 32.5 million units in the second quarter of 2014 (2Q14), a year-over-year decline of -2.9%, according to the International Data Corporation (IDC) Worldwide... Read more
Updated Price Trackers
We’ve updated our Mac Price Trackers with the latest information on prices, bundles, and availability on systems from Apple’s authorized internet/catalog resellers: - 15″ MacBook Pros - 13″ MacBook... Read more

Jobs Board

*Apple* Retail - Multiple Positions (US) - A...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
Position Opening at *Apple* - Apple (United...
…customers purchase our products, you're the one who helps them get more out of their new Apple technology. Your day in the Apple Store is filled with a range of Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
Position Opening at *Apple* - Apple (United...
**Job Summary** At the Apple Store, you connect business professionals and entrepreneurs with the tools they need in order to put Apple solutions to work in their Read more
Position Opening at *Apple* - Apple (United...
**Job Summary** The Apple Store is a retail environment like no other - uniquely focused on delivering amazing customer experiences. As an Expert, you introduce people Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.