TweetFollow Us on Twitter

Jovis, a Database Engine

Volume Number: 14 (1998)
Issue Number: 4
Column Tag: Tools Of The Trade

Jovis, a Database Engine in a Tiny Package

by Edward Ringel

A robust database engine for HyperCard and other XCMD compatible environments

Introduction

Knowledge base development, particularly contract or in-house development, does not require a C, Pascal or C++ environment. To the contrary, many corporate databases and commercially deployed knowledge bases are well supported by database languages such as Fourth Dimension. Other knowledge bases use an authoring front end along with an attached database engine. For example, I use a product called Scientific American Medicine, a complete electronic textbook of internal medicine, that is extensively cross referenced and searchable. It was developed with a MacroMedia Director front end. High level, programmable authoring environments such as HyperCard, SuperCard, and Director can be particularly appropriate when the knowledge base includes pictures, sounds, and videos. These environments are inherently multimedia capable and require little programming knowledge to play a QuickTime clip or show a PICT.

Jovis, by DAS Works, is an extended XFCN that provides broad relational and architectural database capabilities for environments that support XCMD's and XFCN's. This is a comprehensive, well documented product that can support knowledge base development and more traditional database functions in a number of different user settings.

Out of the Box

I received a single disk, a serial number, and a big book. The product comes as a single user SDK or an individually configured Client/Server product; I was sent the single user product for review. In order to use Jovis, I needed to install the product into a HyperCard stack. I could not install the XFCN's into HyperCard itself. Installation, rather than execution is protected by the serial number. (Licensing is addressed later.) The code I used is 68K based and is just under 400K. A PPC version is also available if requested.

The documentation consists of a 16 lesson tutorial and extensive documentation of the various calls. As with most good documentation, the tutorial builds nicely upon itself and is easy to follow. DAS Works does not supply step by step "solutions" to the tutorials; this forces the reader to actually work through the projects to see if they work. The demo supplied with the product actually is a culmination of the tutorials and is a real world example. The lessons address both the relational and architectural capabilities of the product. An introduction also is provided to show some of the intricacies of multi-user issues such as record locking and transactions.

The reference section comprehensively addresses the Jovis calls. Each entry describes the syntax of the call, provides an example, describes the action of the call, and offers relevant comments.

Although a tutorial for Jovis is provided, there is little in the way of more complex examples or a section on "putting it all together." I think they must assume that the user has a good idea of how to use a database. The tutorial teaches the nomenclature and specifics of this particular environment, but does not address design or the management of a complex environment.

The Product

Jovis supports a comprehensive set of relational commands and structures. Relational file creation and open/close operations are very simple and straightforward. Physical files on disk are referred to as "collections," and can contain multiple tables ("relations") and indices. Architectural files are flat file structures that allow the storage, indexing, and rapid retrieval of arbitrary size binary objects (Binary Large Objects, or BLOBs.)

Relation and index construction within a collection requires some work and programming, as with any database system. Jovis offers a shortcut to field and index creation by permitting the creation of a field list or index list. Conceptually, this is like a STR# resource that is then read into the create function, but it is supported as a text string within the scripting language of the front end environment.

Reading and writing records can be performed from script variables or directly into fields in a card or background. Large amounts of data can be read directly into records by an ImportData command. This can be particularly valuable for filling a knowledge base once the structure has been designed and created. There also is an ExportData command.

Obviously, an important feature of a relational engine is the ability to perform a complex search. Jovis does this well. There is a nice section in the tutorial that describes the various comparison operators and how to create compound selection criteria. Jovis supports range searches and the creation of selections. Multiple selections for a given relation are permitted. Merges, which are the same as SQL joins, are supported as a two step process. Selections are first created and then merged. The tutorial completely explains this process.

Record locking and transactions are supported for the multiuser version. There is a section on how the Jovis server works at a file level, but the manual does not teach you how to undertake the design and deployment of a shared, multiuser database system. Calls provided, however, will permit the knowledgeable user to implement a robust, safe multiuser database.

The architectural commands are as important as the relational instructions. Multimedia developers will make heavy use of BLOBs and managing these objects is critical. One very nice feature of Jovis is its ability to embed an architectural file within a relational file, permitting linkage of relational records to architectural indices. As with the relational commands, there is a series of tutorials that teaches the user how to manipulate flat file constructs in the Jovis environment. The tutorial specifically teaches how to use architectural and relational commands and constructs together, which for many developers may be the heart of the product.

Using Jovis

Jovis can be used in any XCMD compatible environment. I tested Jovis in a somewhat older version of HyperCard as well as the current version. It also will run in SuperCard, Director, and Oracle Media Objects. Jovis has an initial startup memory requirement of 512K over and above those of the scripting environment. In some cases, the larger the database the greater the memory requirement.

I found the product difficult to benchmark in a meaningful way. Particularly in a multimedia setting, with various scripting environments and different hardware configurations, any comparison might well be irrelevant to the user/programmer. My overall impression was that performance was more than adequate.

Use of the product requires that the programmer follow some conventions regarding the need for the programmer to create several global variables which would then be for the use of the database engine rather than the stack. One very nice feature of this product is very good error management. In addition to the XFCN managing and communicating errors, it is possible for your script to intercept and handle error conditions as well. The ability to provide more than "plain vanilla" dialogs reporting an error condition with graceful recovery is critical to a commercial product.

It was difficult to pick a representative complete script to give a flavor of how the product is used. In the end, I simply took the first one in the tutorial, demonstrating creation of a relational file:

function CreateNewFile
   global myDB, JovisErrorCode
   --myDB is reserved for exclusive use by Jovis 
   if myDB = empty then
      put "Jovis" into myDB
   --initialize myDB
      get Jovis("CreateCollection", "myDB")
      --all calls to Jovis are in the format get Jovis(),
      --with the first parameter the action selector
      if item 1 of JovisErrorCode = "error" then
         answer JovisErrorCode
         put empty into myDB
         return "false"
      else if item 1 of JovisErrorCode = "Warning" then
         answer JovisErrorCode
         put empty into myDB
         return "false"
      end if
    else
      return "false"
   end if
   return "true"
end CreateNewFile

Here are some other brief examples:

Create a relation named customers in the file myDB:

on CreateDemoRelation
   get Jovis("CreateRelation", "myDB", "Customers")
end CreateDemoRelation

Create an text index of 8 character length named Last_Name in the relation Customers in the file "myDB"

on CreateTextIndex
   get Jovis("CreateIndex", "myDB", "Customers",  
                     "Last_Name", "text", 8)
end CreateTextIndex

Perform a selection searching on Last_Name in our hypothetical Customers database:

on DemoSelect

   ask "Enter last name to set selection to:"
   if the result = "cancel" then exit DemoScript
   put it into Last_Name
   Put "Field Last_Name = ["& Last_Name &"]" into Criteria
   Put "Last_Name, phone, Customer_ID, Account_Start"  
                  into FieldList
   get Jovis("Set Selection", "myDB", "Customers", 
                  fieldList,Criteria)
end DemoSelect

While I have not commented this code, I think the general sense of the steps and syntax is apparent.

Licensing and Costs

This product has a somewhat complex licensing arrangement. The basic price for a single user license (single computer for non-commercial distribution) is $345. Thus, the person creating a database for personal use is spared the expense of a full commercial license. If the database will be used on more than a single computer, an additional fee of $350 is required. This additional fee covers everything from unlimited commercial distribution to simultaneous use of the single user product on a second computer in the same office. Hypothetically, a knowledge base with a HyperCard front end and a Jovis database that sells 1000 copies still only costs you $695 in license fees to DAS Works. Not too shabby.

The server version is more expensive, but again within reason. The basic multiuser package comes with a server and a three user license and costs $435. Each additonal user costs $85. The server product is protected by a hardware ADB lock. Licenses for the commercial distribution of a multiuser product developed with Jovis are handled on a case by case basis.

The Bottom Line

Jovis is a relational and flat file engine that lives in the XCMD world. It has a complete set of relational commands nicely complemented by architectural commands. The two schemes can be used together to create traditional relations supplemented by BLOBs: a perfect combination to implement multimedia presentations. Although difficult to judge, it appears that performance is more than adequate. The pricing scheme has many steps but is fair. Were I developing multimedia on Macintosh, I would give this product serious consideration to implement my work.

It would be very helpful if DAS Works created a "User Manual." The reference manual and tutorial are both quite good. However, once the user is acquainted with the product, he or she will want a document on putting it all together without needing to browse the tutorials again, and something more cohesive than a function call reference. Additionally, Jovis is sufficiently different in structure and nomenclature from SQL that some in depth solutions to complex examples are warranted. Finally, I respectfully suggest a set of text files containing the scripts for each of the tutorials.

Products Reviewed

Jovis Single User SDK version 1.04. DAS Works, Inc. 250 West 104th St, Suite 84. New York, NY 10025-4292. Toll free (800) 972-2483. Fax (212) 663-4503. email to info@dasworks.com or sales@dasworks.com. There is a website at http://www.dasworks.com/.


Ed Ringel is Contributing Editor for product reviews for MacTech Magazine. When he's not working at the computer or enjoying the Maine lakes and woods, he's a respiratory and critical care physician in Waterville, Maine. He can be reached at eringel@mint.net.

 
AAPL
$104.83
Apple Inc.
+1.84
MSFT
$45.02
Microsoft Corpora
+0.64
GOOG
$543.98
Google Inc.
+11.27

MacTech Search:
Community Search:

Software Updates via MacUpdate

Delicious Library 3.3.2 - Import, browse...
Delicious Library allows you to import, browse, and share all your books, movies, music, and video games with Delicious Library. Run your very own library from your home or office using our... Read more
Art Text 2.4.8 - Create high quality hea...
Art Text is an OS X application for creating high quality textual graphics, headings, logos, icons, Web site elements, and buttons. Thanks to multi-layer support, creating complex graphics is no... Read more
Live Interior 3D Pro 2.9.6 - Powerful an...
Live Interior 3D Pro is a powerful yet very intuitive interior designing application. View Video Tutorials It has every feature of Live Interior 3D Standard, plus some exclusive ones: Create multi... Read more
The Hit List 1.1.7 - Advanced reminder a...
The Hit List manages the daily chaos of your modern life. It's easy to learn - it's as easy as making lists. And it's powerful enough to let you plan, then forget, then act when the time is right.... Read more
jAlbum Pro 12.2.4 - Organize your digita...
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
jAlbum 12.2.4 - Create custom photo gall...
With jAlbum, you can create gorgeous custom photo galleries for the Web without writing a line of code! Beginner-friendly, with pro results Simply drag and drop photos into groups, choose a design... Read more
ExpanDrive 4.1.7 - Access remote files o...
ExpanDrive builds cloud storage in every application, acts just like a USB drive plugged into your Mac. With ExpanDrive, you can securely access any remote file server directly from the Finder or... Read more
OmniOutliner Pro 4.1.3 - Pro version of...
OmniOutliner Pro is a flexible program for creating, collecting, and organizing information. Give your creativity a kick start by using an application that's actually designed to help you think. It'... Read more
Evernote 5.6.2 - Create searchable notes...
Evernote allows you to easily capture information in any environment using whatever device or platform you find most convenient, and makes this information accessible and searchable at anytime, from... Read more
OmniOutliner 4.1.3 - Organize your ideas...
OmniOutliner is a flexible program for creating, collecting, and organizing information. Give your creativity a kick start by using an application that's actually designed to help you think. It's... Read more

Latest Forum Discussions

See All

A Few Days Left (Games)
A Few Days Left 1.01 Device: iOS Universal Category: Games Price: $3.99, Version: 1.01 (iTunes) Description: Screenshots are in compliance to App Store's 4+ age rating! Please see App Preview for real game play! **Important: Make... | Read more »
Toca Boo (Education)
Toca Boo 1.0.2 Device: iOS Universal Category: Education Price: $2.99, Version: 1.0.2 (iTunes) Description: BOO! Did I scare you!? My name is Bonnie and my family loves to spook! Do you want to scare them back? Follow me and I'll... | Read more »
Intuon (Games)
Intuon 1.1 Device: iOS Universal Category: Games Price: $.99, Version: 1.1 (iTunes) Description: Join the battle with your intuition in a new hardcore game Intuon! How well do you trust your intuition? Can you find a needle in a... | Read more »
Ravenous Rampage (Games)
Ravenous Rampage 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: | Read more »
Partia 2 (Games)
Partia 2 1.0.1 Device: iOS Universal Category: Games Price: $5.99, Version: 1.0.1 (iTunes) Description: Partia 2 is a SRPG (Strategy Role-playing) video game inspired by Fire Emblem and Tear Ring Saga series. In a high fantasy... | Read more »
Puzzle to the Center of the Earth Review
Puzzle to the Center of the Earth Review By Campbell Bird on October 23rd, 2014 Our Rating: :: SPELUNKING PUZZLESUniversal App - Designed for iPhone and iPad Do some puzzles to make some platforms in this smart and fun free-to-play... | Read more »
Sleep Attack TD Review
Sleep Attack TD Review By Jennifer Allen on October 23rd, 2014 Our Rating: :: A TRUE TWISTUniversal App - Designed for iPhone and iPad Sleep Attack TD is a tower defense game with a difference – you can rotate the layout – and it’s... | Read more »
Mecanic (Education)
Mecanic 1.0 Device: iOS Universal Category: Education Price: $1.99, Version: 1.0 (iTunes) Description: Plates, screws, wheels ... Everything you need to achieve whatever you want... MECHANICWith 'MECANIC' kids will have fun... | Read more »
Earn Your Master Camper Badge in Camp Po...
Earn Your Master Camper Badge in Camp Pokemon Posted by Jessica Fisher on October 23rd, 2014 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
Garruk Gets His Revenge in a New Magic 2...
Garruk Gets His Revenge in a New Magic 2015 Expansion, Coming This November Posted by Jessica Fisher on October 23rd, 2014 [ permalink ] | Read more »

Price Scanner via MacPrices.net

Save up to $125 on Retina MacBook Pros
B&H Photo has the new 2014 13″ and 15″ Retina MacBook Pros on sale for up to $125 off MSRP. Shipping is free, and B&H charges NY sales tax only. They’ll also include free copies of Parallels... Read more
Apple refurbished Time Capsules available sta...
The Apple Store has certified refurbished Time Capsules available for up to $60 off MSRP. Apple’s one-year warranty is included with each Time Capsule, and shipping is free: - 2TB Time Capsule: $255... Read more
Textilus New Word, Notes and PDF Processor fo...
Textilus is new word-crunching, notes, and PDF processor designed exclusively for the iPad. I haven’t had time to thoroughly check it out yet, but it looks great and early reviews are positive.... Read more
WD My Passport Pro Bus-Powered Thunderbolt RA...
WD’s My Passport Pro RAID solution is powered by an integrated Thunderbolt cable for true portability and speeds as high as 233 MB/s. HighlightsOverviewSpecifications Transfer, Back Up And Edit In... Read more
Save with Best Buy’s College Student Deals
Take an additional $50 off all MacBooks and iMacs at Best Buy Online with their College Students Deals Savings, valid through November 1st. Anyone with a valid .EDU email address can take advantage... Read more
iPad Air 2 & iPad mini 3 Best Tablets Yet...
The new iPads turned out to be pretty much everything I’d been hoping for and more than I’d expected.”More” particularly in terms of a drinking-from-a-firehose choice of models and configurations,... Read more
Drafts 4 Reinvents iOS Productivity App
N Richland Hills, Texas based Agile Tortoise has announced the release of Drafts 4 for iPhone and iPad. Drafts is a quick capture note taking app with flexible output actions. Drafts 4 scales from... Read more
AT&T accepting preorders for new iPads fo...
AT&T Wireless is accepting preorders for the new iPad Air 2 and iPad mini 3, cellular models, for $100 off MSRP with a 2-year service agreement: - 16GB iPad Air 2 WiFi + Cellular: $529.99 - 64GB... Read more
Apple offering refurbished Mac Pros for up to...
The Apple Store is offering Apple Certified Refurbished 2013 Mac Pros for up to $600 off the cost of new models. An Apple one-year warranty is included with each Mac Pro, and shipping is free. The... Read more
Select MacBook Airs $100 off MSRP, free shipp...
B&H Photo has 2014 a couple of MacBook Airs on sale for $100 off MSRP. Shipping is free, and B&H charges NY sales tax only. They also include free copies of Parallels Desktop and LoJack for... Read more

Jobs Board

*Apple* Solutions Consultant - Apple Inc. (U...
…important role that the ASC serves is that of providing an excellent Apple Customer Experience. Responsibilities include: * Promoting Apple products and solutions Read more
Senior Event Manager, *Apple* Retail Market...
…This senior level position is responsible for leading and imagining the Apple Retail Team's global event strategy. Delivering an overarching brand story; in-store, Read more
*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
Project Manager / Business Analyst, WW *Appl...
…a senior project manager / business analyst to work within our Worldwide Apple Fulfillment Operations and the Business Process Re-engineering team. This role will work Read more
*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
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.