SAP R/3 is perhaps the best known ERP (Enterprise Resource Planning) system on the market. Originally dating back to the 1970s, it took the then-controversial approach of combining various business functions into one application and database.
Originally, R/2 was implemented atop mainframe databases like DB/2 , Adabas, and IMS.
In the 1980s, SAP designed a new architecture for the new R/3 system using a multi-tiered Client/Server architecture, with data storage on a database server running some relational database, application code, written in their ABAP/4 language, running on a set of application servers.
SAP intended to keep a degree of vendor-independence; the application server software can run on a number of platforms that have included several Unix flavors, VMS, and Microsoft Windows NT, whilst they have supported a variety of relational databases, including Oracle, Adabas, Informix, Microsoft SQL Server. Front end software uses their own proprietary protocols atop TCP/IP, and has run on various platforms.
I used to do R/3 work, but am no longer in this market. I no longer have terribly many useful contacts, so if you're trying to staff a project, it probably isn't worth contacting me.
This provides people with OSS IDs access to some R/3 documentation not directly available through OSS. (If you don't understand this, you probably can't use this.)
Access to SAPnet - Needs OSS ID, password
This was once the "Heidelburg" project that sought to create an R/3 Lite product.
They found the interesting (and not overly surprising) result that smaller enterprises aren't necessarily that much less sophisticated in their needs, and that stripping down R/3 wound up being pretty counter-productive.
This is not unlike the way that if you introduce various flavors of investment vehicles like mutual funds, 401(k)s, IRAs, and RRSPs, "personal finance" can require sophisticated investment analysis tools that typically aren't needed by small businesses.
They are instead working on ways of speeding the process of configuring "full" R/3 systems.
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