Be the change you wish to see, and all those who are ready will respond. There’s really no way for you to know who the “right” people are

In Udi’s article on MSDN;
http://msdn.microsoft.com/en-us/library/bb245672.aspx

He writes the following:

Note that while a service may consume other services asynchronously, this consumption does not necessarily mean that it cannot expose a synchronous interface. Google and Amazon do exactly that. The Web services that they expose are synchronous in nature but it has no effect on their autonomy.

The article is a very good read. Recommended

PS Love these posts but the intervals in between them are killing me lol

When it comes to personally identifying information, often we can comply with the privacy laws by just scrambling the data.

I’ve just opened registration – http://adsd-sydney-2012.eventbee.com/

Do we really want to store everything from now to eternity?

If we don’t, we have to delete something. Like orders older than 10 years or customers who haven’t bought anything in 2 years.

Or stock data from 5 years ago. Storing personal data of ex-employees is probably illegal in many countries, they have to be deleted as soon as employment ends.

So: As a blanket idea ‘Do not delete’ is very bad idea: It will cause massive problems sooner or later.

I agree. Most forms of conflict are counterproductive.

Cheers
John

Say you are analysing a business and you have identified two candidate ABCs that own distinct data and provide unique functionality that is reused by a number of systems (not necessarily the same set of systems). You then identify a third ABC, that would manage some data of its own, encapsulate significant business logic and could be used by another set of systems. However, you realise this new ABC consumes some of the data currently assigned to those other ABCs. So we appear to have one ABC that is reliant on the detailed data that is managed by other ABCs (not just the correlation ids exposed by the other ABCs). Is this situation symptomatic of a poor ABC split or quite normal?

If it is quite normal, have you any suggestions as to how the third ABC retains its autonomy? If it is only passed correlation Ids, then it will be reliant on the other ABCs in order to retrieve the detail it needs, or it could access their data stores directly or it could keep a read only copy of the data it needs. The alternative whereby, the systems using the new ABC have to pass in the extra detail when they want some function performed, means that those systems need to know what data to pass in.

In Araon’s case this could be a Portfolio ABC, Stocks ABC and a Financial Forecasting ABC where the Finacial Forecast ABC will consume the detail from a portfolio along with detailed stock market data, apply some complex business rules (such as tax treatments, growth assumptions etc. etc.) and generate a forecast.

There’s always a problem in dealing with a very shallow description of a problem domain. Details matter and should influence the breakdown.

More generally, reporting is usually handled in 2 ways. The first is via a composite UI (things usually not thought of as reports). The second is via a data dump to excel where users can do whatever they want with the data – ad-hoc reporting.

A third, and interesting alternative to reporting, is to think of what real world event users are trying to see by using reports and then make the system surface that explicitly.

A Portfolio ABC that knows what investments a client has. A Stock ABC that knows the details of individual stocks (such as name and historical price). He might then have an Investment Tracking System that uses both of these ABCs to allow a client to maintain his portfolio and look at its current value. If this system should then provide some significant functionality such as the creation of a detailed performance report, where might that report be generated? Would a third ABC be introduced… Performance Report ABC?

If Performance Report ABC is required, would you expect the system to ask for a report based on a whole set of data that the system passes in (meaning the system needs to know what data is relevant to the Performance Report ABC) or would you expect the system to pass in a set of identifiers and expect the Performance Report ABC to retrieve the data it needs from the other ABCs (which would mean the Performance Report ABC is not so autonomous)…. OR does this linkage indicate you have not got the ABC divide correct?

Some systems can be parallelized – most, only up to a point.

“Proven” ?

Infinity is impossible to prove by definition. Also, as anyone whose built systems of scale will tell you, there’s a very big difference between theory and practice.

I’m all for getting people to start moving in the right direction, even if that means some hyperbole *when necessary*.