Thursday, 22 October 2009

Unused and Duplicate Prompts

We have been developing our products for close to 20 years now and one of the consequences has been that we have found quite a few unused and duplicate prompts in the models. We also have a multiple model architecture and a policy of migrating the entire data model to each of the development models. This results in all of the prompts also being duplicated (and unused) in all of the models.

Apart from having a large number of redundant prompts in the models, it can also make the selection of prompts in the window/screen designer tedious because the large lists of unused and duplicate prompts makes locating the desired prompt harder.

There is a Gen function in the toolset to delete unused prompts, but this requires the model to be downloaded, and ours are too big. It will also not get rid of duplicates.

We have therefore written a new genIE function to both delete unused and consolidate duplicate prompts.

The result is faster downloads because you are not downloading extra prompts and also easier selection of existing prompts in the window/screen designer.

Thursday, 1 October 2009

RI Trigger Impact Analysis

The previous post discussed the need to regenerate programs that call changed RI triggers. The difficulty is in performing this impact analysis.

The Gen model does contain associations between action blocks and RI triggers (using IMPUSE associations if you are familiar with the Gen schema), but the important point to note is that these associations are maintained by the code generators. This means that if you change the data model, the IMPUSE association data in the model is not accurate until you have regenerated the affected code, which makes it useless in helping you understand what you need to regenerate!

We faced this issue when developing the impact analysis process that GuardIEn performs when it detects data model changes. To work out what RI triggers are directly affected by a data model change is straight forward, but the consequential impact on other triggers and action block / procedure steps involves a complex navigation though the data model, following cascade delete chains for example. It is also affected by the choice of generated or DBMS enforced RI rules.