20.9.82

Codasyl/BCS DBAWG

The Burn

DBAWG (Database Administrator Working Group) is a long-established working group of the BCS which is also affiliated to CODASYL (Conference on Data Systems Language - that influential body to which we owe such delights as Cobol and IDMS). Its membership is eclectic and disputacious. Many innovations in the database world have originated in or been subtly moulded by its argumentative members (the IDMS Fortran Interface and the independent storage schema being two notable recent examples).

I was invited to attend this meeting as an observer. The meeting was hosted by Aberdeen University at the Burn, a charming country house on the banks of the North Esk (but unfortunately out of the Salmon-fishing season). Other academic bodies represented included the Open University, Edinburgh and Sheffield Poly; manufacturers represented included Philips and Univac; software house CACI and SCICON were also represented as were users such as John Brown Engineering and MOD.

It soon became evident, however, that the members of the group (25 in all) were present in purely personal capacities. DBAWG's current projects are the definition of an architecture to support distributed databases and the extension of CODASYL systems to include access control; its two current subgroups reflect this division.

I sat in on discussions of both subgroups and also on the major topic of the whole meeting, which was the proposed ANSI DBCS specification derived from Codasyl. Of the two subgroups, work on the distributed architecture is well advanced and most of the time was spend clarifying and optimising the expression of the group's proposals in a working paper. Work on access control is less well advanced however: an initial model, based on ISO 'information systems' concepts, has been floundering for the last two meetings on matters of definition. Quite what an 'action' (to or by which access is to be controlled) is and at what level of primitiveness it exists has been the subject of two papers, both now rejected.

In discussing the ANSI paper, several worthwhile criticisms emerged, notably the absence of compound data structures and of language-dependent facilities at the subschema level.