Visual DataFlex: Difference between revisions
Content deleted Content added
Asckey Data Services Ltd, Data Access UK Channel Partners |
|||
| (16 intermediate revisions by 12 users not shown) | |||
| Line 1: | Line 1: | ||
#Redirect [[DataFlex]] |
|||
'''Visual DataFlex''' is a [[4GL]] windows [[programming language]] by [[Data Access (company)|Data Access]], targeted at creating [[database]] and client-server type programs. |
|||
== Architecture == |
|||
Visual DataFlex has a 3-layer architecture: |
|||
;Bottom layer: At this level you have the database tables. |
|||
;Middle layer: Here you have Data Dictionary classes which are the core of the product. Data Dictionaries define the business rules for each table in your database. For example, when orders are saved a customer's balance can be adjusted and the balance tested against the customer's credit limit. An error can be raised if the customer's balance would exceed the allowable credit limit. Rules for saving, editing, deleting, or finding records are defined too. For example, you may not be allowed to delete an inventory item because there is history for it i.e. there are sales or purchases of the item. Finding of certain records can be limited to users who have the required credentials. |
|||
;Top layer: A graphical user interface ([[GUI]]) that allows users to enter, find, create, modify, or delete data. The UI will respect all of the business rules defined in the Data Dictionary classes. |
|||
== History == |
|||
{{cleanup|section|date=February 2008}} |
|||
Data Access Worldwide of Miami, USA is the company behind the studio and language and built its business up around the console mode [[DataFlex]] language which was released prior to [[MS-DOS|DOS]] and competed with [[dBase|dBase II]] in early microcomputer technology. The first attempt at a windows product was ''DataFlex for Windows'' which failed as it was a sort of windows bolted on top of DOS product. Then they released Visual DataFlex 4.0 in 1997 which allowed users to write native 32 bits Windows applications. Every 6 months a new revision level is released. Visual DataFlex is now in revision 17.0, named VDF 2012<ref>{{cite web|url=http://www.visualdataflex.com/features.asp?pageid=1073|title=Visual DataFlex Features-Visual DataFlex 2012/17.0 |publisher=Visualdataflex.com |date= |accessdate=2012-07-05}}</ref>, and features a datadictionary layer of business rules which is of dual use with the windows product and the webapp extension. |
|||
== References == |
|||
<references /> |
|||
== External links == |
|||
* [http://www.visual-dataflex.com Official website] |
|||
* [http://www.vdfwiki.com vdfwiki.com] |
|||
* [http://support.dataaccess.com/forums/ Support forum] |
|||
* [http://www.vdf-guidance.com Visual DataFlex open source website] |
|||
* [http://http://www.visual-dataflex.co.uk] |
|||
[[Category:4GL]] |
|||
{{compu-lang-stub}} |
|||
[[ms:Visual DataFlex]] |
|||
[[ru:Visual DataFlex]] |
|||
Latest revision as of 16:13, 19 March 2017
Redirect to: