Bert Verhees wrote: >> Dear group >> >> I've a question about ? what is the experience implementing openEHR in >> opensource database like mysql or progreSQL in a hospital of 500 beds? > > I don't think there will be much difference as long as it comes to an > SQL-based implementation. The benchmarks for ANSI-SQL-handling MYSQL of > SQL-server or Oracle are more or less comparable. > It is very easy to test, you can also take a look at TPC-benchmarks, > because you can regard the OpenEhr database-use as a rather complex use > with 50 to 100 tables (depending on the architecture-specifics) > > But when you look to other ways, f.e. object-oriented databases, like > Matisse or Cache, or XML-features of databases, then you bind yourself to > vendor specific features, then it is another story, and not easy to > determine what is a good choice. > > There is not much discussion on this subject, good that you bring it up. I > hope others will say something about this subject.
The key issue is no so much what database back-end to use, but rather what to use or write as the openEHR layer (kernel and query system). I'm told that there are various closed-source, proprietary implementations of openEHR (e.g. by Ocean Informatics) which can use an SQL back-end, but only one open-source implementation, by ACode in Sweden, which is on the openEHR.org web site. But what is the current status of this implementation - it is rather hard to determine exactly what bit work, what bits have been fully tested and what is left to be done, short of installing it, looking through its source code and writing one's own tests. The latest release notes for it at http://svn.openehr.org/ref_impl_java/TRUNK/readme.txt say: ########## Java openEHR Implementation project ----------------------------------- VERSION Release-1.0.1 RC STATUS Based on openEHR release 1.0.1 RC and implemented Reference Model - EHR, EHR Extract, Demographics, Common, Data Structures, Data Types and Support, and Archetype Object Model, openEHR Archetype Profile. Besides, support for archetypes based object creation has been added into Archetype Object Model classes. The work is still in progress. The intention is to have complete implementation of openEHR Reference Model and Archetype Object Model, with support for archetype based object creation and validation. ########### I'm not sure whether that means it supports queries or not - I suspect not. So for an open-source implementation of openEHR, it looks like, as at August 2007, one has to either wait an indeterminate length of time for the ACode implementation to be completed or one has to write an entire openEHR kernel (and test and validate it, which is the more time-consuming part) oneself. Is that correct? I must save this email for re-use because I have been asking this same question for over three years now... Tim C
