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SAP is really a collection of business processes implemented in software. No shock there. In some cases, these processes are implemented in code. Yech. In other cases, these processes are implemented as simple or complex finite state machines dynamically driven by data or metadata; unfortunately, these state machines are written on different programming models, using sometimes very different (domain-specific) languages and technologies. Generally speaking, these state machines are integrated (or can be integrated through customization) in various ways that can be very interesting to enterprises, allowing for processes like "build to order" to function properly (which integrates "order" with "collection" with "dunning" with "schedule" with "manufacture" with "ship" with ...).
Because these processes are so diverse, and have been implemented literally over a thirty year stretch in time, there is not a lot of consistency in their underlying technologies and programming models. With all this inconsistency, it is not straightforward to produce and consume events, which makes these processes hard to configure, integrate, and extend.
Event-based systems are not foreign to SAP, but (modern) event-based technology (at least within the applications) is. Anyone who has used ARIS to do the design of business processes for SAP implementations has probably used "event-driven process chains" (EPCs) to describe processes; implementing the event connections, however, has often/mostly been a process of writing custom code. There is no publish/subscribe bus for (most important) SAP events, thus there are no (substantial) event publishers or subscribers in the SAP application suite.
If SAP were to undertake a rewrite of its applications, it would have the opportunity to implement events in a consistent way in the applications. I am not certain if this has been done with Business ByDesign ("ByD"), which was a project which undertook to rewrite some of SAP's applications, but very few mySAP Business Suite customers will be replacing their mySAP suites with ByD any time soon.
If, on the other hand, SAP were to undertake a rewrite of its application server tier to replace all calls to a database with calls to "HassoDB" (the in-memory database that got so much attention at SAPPHIRE this week), SAP would have the ability to simultaneously event-enable its product essentially with little to no additional effort. If HassoDB understands that an object is being stored, updated, or accessed, HassoDB could publish an event - and that event could be consumed by new applications that speed up integration between business processes, allow the insertion of new business processes, or that simply generate alerts for users.
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SAP even has a design for such a capability: SAP Live Enterprise from SAP's Imagineering team.
How could this capability be deployed? Well, imagine that a sales person gets an alert every time their customer makes a payment, is late with a payment, submits a complaint or service request, or places an order on-line. Or that a salesperson sets up an "auto-responder" for those events, thanking the customer or asking her for feedback as appropriate. Event-based capabilities would greatly speed up and improve service.
Another example could be in integrating business processes. Rather than hard-coding the "on-boarding" process for a new employee, there could be an event-driven integration. The hiring process could generate an event when an employee's starting date is set; other processes could subscribe to that event, and do the appropriate processing, including reserving an office, preparing the HR orientation, ordering a company credit card, requesting an entry badge, or assigning and configuring a computer. Whenever the on-boarding process changes, rather than editing the process definition, taking the application down in the process, and restarting it, instead an administrator would just load a new action and subscribe it to the appropriate event.
Finally, how will customers license the in-memory database? Will they have to buy it or will it be included in maintenance? If it is the latter, and if the in-memory database can be made compatible with older versions of SAP, then this would be substantial justification for the maintenance fees SAP has charged customers over the years. Even if customers have to separately license and pay for this capability, if it is made compatible with all versions of mySAP under maintenance, that would be a huge benefit for customers. I'm looking forward to SAP bringing "HassoDB" to market. With the help of the database gurus at Sybase, I think it is possible that in-memory will finally come to "Big Data" enterprise problems.