Hi Chris,
Your expectations are one of the reasons that I do not think WinDP will ever be, or will ever be in the form that people will want or expect. In the DOS age applications generally did not need to support communication between other programs, or to share services with other programs, or to have functionality outside what the original developers planned. WP's Shell was way ahead of its time in this respect, but so small compared to the extremely wide range of functionality that software is expected to have these days. For DP to come out in a Windows format with all the functionality that would be expected I think is extremely unlikely. However, DP for DOS as a specialist database still is extremely valuable and certainly fits into modern day Windows, MAC or Linux applications; just not at the front end on these machines. In fact the way DP for DOS works it forces you to go into the most modern means of using databases. Although I still write desktop applications in Microsoft Access the typical desktop database application is all but dead whether it be Windows or DOS. DP well fits into what is known as a multi-tiered or n-tiered architecture. n-tier is a client-server architecture where the end-user client application; the application processing and the database management are separate processes. The tasks of a tier is generally performed in physically independent piece of software. On in the other hand Microsoft Access and other desktop file databases including the original DP paradigm, the user interface, application processing and database management all seems to coexists in what is better described as a multilayered approach, where the tasks of each layer exist are performed within the same program. The problem with the multi-layered approach is that the expectations that various prospective users will have for each layer are now so vastly different that it really exceeds the capacity of any vendor to fill its needs, and as well as that the internet has brought a networking model that is not supported by this multilayer approach. You often hear people talk about other desktop multi-layered applications being used on the web, such as "we just use Microsoft Access as a backend database": When they do this, they are no longer using two of the Access layers, but instead use one layer purely for database management. They then write all the other functionality with a user-interface (often HTML) and a middleware component (often PHP, ASP or VB.NET). They write protocols whereby one layer can efficiently communication with the next layer, and do not need to be concerned with how the nonadjacent layers work. Microsoft Access in this type of database roles works ok, but it does have many limitations, for a start it's not a great multi-user database manager - its locking mechanism gets into too much trouble. Used this way it lacks many of the features that makes it such as easy desktop program, but it also misses out on some other important feature that a desktop fil database does not need. In the database world you really need a program that can run Views. Stored procedures and Triggers. Found in modern database managers such as Microsoft SQL server, Oracle, PostgresSQL etc. Microsoft Access can only either return table data or handle simple Views.. Views are queries where a either a subset of data is returned or where tables are joined, often using SQL SELECT statements. Stored Procedures are often a sequence of SQL queries that in combination can perform tasks such as inserting data into multiple tables, deleting data or for executing other programming code. Database triggers is procedural code that is executed in response to data being added, deleted or changed. In web driven DataPerfect you basically forego the user interface layer. The interface for other adjacent layers is via the Transaction Log for input and via reports for business logic and output. So in comparison to say a SQL database, in DP a View is implemented by way of a simple database report, and a Stored Procedure is just a more complex report. Although DP doesn't have a good analogy to Database Triggers there are a number already built in, which in other environments you would have to carefully built. For example, keep-a-total's in other database systems need to be implemented as a set of relatively complex procedures, whereas in DP it is just easily done through Panel design . Similarly cascade deletes are more cumbersome in many environments as are calculated fields. One feature which is lacking in DP is the ability to create Pass Through Queries, where the code to be executed is crafted at the client application, and pushed through to the database program. However unless you are very careful you can often create security problems, by allowing client programs unfettered access to the data, so if you do then you have to build far more complex and robust backend applications. You really have no limit to the types of applications that can be built with DP, and the types of front end applications. The client programs can be web deployed HTML, Flash, Flex, or they can be stand alone applications such as VB, VB.NET, Java, Adobe AIR etc. DP's reports can often be far more useful than Stored Procedures , and so entire business logic ca be built with reports, making it one of the middleware tiers. You do however need another tier to handle the client requests, and output back to the client; I use Perl for this. I generally build my DP applications as web applications, but you could quite easily build applications with other applications in the front end. You do not need a web server to create Windows applications, it would be quite possible to build say a desktop application using Microsoft Access with DP in the background as the database manager. It would probably take a lot more work than just using Access built in JET databases but it could be done. At the moment I feel like Robinson Crusoe, I wish others would start having a go at using DP for web databases. It would certainly be great to be able to draw on other peoples experiences with it, and to get a collective body o knowledge and expertise around it Bye Brian _____ From: [email protected] [mailto:[email protected]] On Behalf Of Chris Pedersen Sent: Sunday, 15 March 2009 12:09 AM To: [email protected] Subject: Re: [Dataperf] HTML I think for many reasons it would be incredibly useful to be able to execute foreign code. A couple of formats: Click to execute the content of a field - Click to execute an app defined on a field _____ From: [email protected] To: [email protected] Date: Sat, 14 Mar 2009 07:32:00 -0400 Subject: Re: [Dataperf] HTML If user is using windows xp/vista, shell macro can execute IEXPLORE c:\help.htm which loads a page called help.htm. DPMouse can launch the macro. Or you can load a text editor with text help if you don't like html. _____ From: [email protected] [[email protected]] On Behalf Of Chris Pedersen [[email protected]] Sent: Friday, March 13, 2009 9:39 PM To: [email protected] Subject: Re: [Dataperf] HTML Yet, it seems like an easy and important component in the transition to WinDp. Such a product would have to support XML/HTML. Allowing DP to use this as a help documentation would be a good first step. _____ From: [email protected] To: [email protected] Date: Sat, 14 Mar 2009 10:28:01 +1100 Subject: Re: [Dataperf] HTML Hi Chris, I don't think you will get any luck with DP itself on this, however I have heard of a DOS TSR which creates hyperlink of whatever looks like a valid URL's on the screen. I have just gone for a quick search for it on my PC, as I thought I had downloaded it but alas no luck. I can't even remember what it as called, and I didn't even try it, but I thought it could be something useful. It is probably worth searching Google for it. I had a quick search then and couldn't find it, but I think it was on a site with a large number of other DOS utilities. Bye Brian _____ From: [email protected] [mailto:[email protected]] On Behalf Of Chris Pedersen Sent: Saturday, 14 March 2009 9:25 AM To: [email protected] Subject: [Dataperf] HTML I apologize if this is already covered territory. Oft times, I find the required help for a panel exceeds the dos capabilities or convenience of dataperfect. Two questions/suggestions; the first is simpler, the second more of an extension to the first. 1. Is it possible to pass a url in the help panel as a way of passing additional help for the database - procedures (or an index code, so it jumps to the appropriate page). 2. Would it be possible to link an external web page to a field: Ie., when a person clicks on a field, the sidekick browser gets passed a webpage. That webpage has all the help required for the field. Chris _____ HotmailR is up to 70% faster. Now good news travels really fast. Find <http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_70faster_032009> out more. _____ Express your personality in color! Preview and select themes for HotmailR. See <http://www.windowslive-hotmail.com/LearnMore/personalize.aspx?ocid=TXT_MSGT X_WL_HM_express_032009#colortheme> how. _____ Windows LiveT: Keep your life in sync. 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