Writing queries over Visual LANSA Framework objects
You can write query programs that report on the objects in the Visual LANSA Framework (VLF).
The query programs need to execute in VLF-WIN but can report over a VLF-ONE Framework model.
You might use them to produce lists of objects in the Framework, either to locate error situations or to assess development progress, in the same way as you might write queries over the LANSA internal DC@ repository files. You can extract information from the Framework and transform it into other forms or other media.
There are some important restrictions:
- Such programs should never be run in a production or end-user environments. They are tools for the developer in the developer's environment only.
- These programs can access internal VLF properties that are not usually accessible to command handlers or filters.
- The possibility exists that the VLF properties might change in the future. If this happens you might have to change your query programs, usually very slightly.
- These properties are not externally documented. If you don't understand a property or how it works then you may need to put a question onto a forum.
- The VLF properties are read only – they should never be written as you may corrupt your Framework file.
Getting Started
Using the First Query Example
Using the Second Query Example
Using the Third Query Example
Creating Your Own Queries
Other things worth knowing about Query Programs
Examples