From rts Thu Jul 1 09:34:27 1993 Date: Thu, 1 Jul 1993 09:31:07 MST From: "Rick Snodgrass" To: Phayes@cs.uiuc.edu, ahn@cbnmva.att.com, ariav@taunivm.tau.ac.il, b_theodoulidis@mac.co.umist.ac.uk, blakeley@csc.ti.com, boddy@src.honeywell.com, buchmann@dvs1.informatik.th-darmstadt.de, csj@iesd.auc.dk, curtis@cs.arizona.edu, dayal@hplabs.hp.com, dcroft@darpa.mil, dittrich@ifi.unizh.ch, eliop@isosun.ariadne-t.gr, elmasri@cse.uta.edu, fabio@deis43.cineca.it, gadia@cs.iastate.edu, gio@DARPA.MIL, jajodia@sitevax.gmu.edu, jcliffor@is-4.stern.nyu.edu, kaefer@almaden.ibm.com, kia@cs.unlv.edu, kouramaj@cse.uta.edu, krithi@cs.umass.edu, kulkarni_krishna@tandem.com, max@mecan1.maine.edu, mb@cs.ulb.ac.be, mumick@research.att.com, olken@ux5.lbl.gov, ozsu@cs.ualberta.ca, pernici@ipmel2.polimi.it, peuquet@geog.psu.edu, pissinoi@nye.nscee.edu, rts@cs.arizona.edu, schen@nsf.gov, segev@csr.lbl.gov, sharma@snapper.cis.ufl.edu, soo@cs.arizona.edu, srelan@arpa.mil, sripada@ecrc.de, su@pacer.cis.ufl.edu, tcheng@cs.iastate.edu, ted@cm.cf.ac.uk, tsotras@aegean.poly.edu, uztbb@cunyvm.cuny.edu, wells@osage.csc.ti.com, wuu@ctt.bellcore.com Subject: TSQL2 working group Content-Length: 2383 Status: RO X-Lines: 52 In this message I outline a structure for the short term design of a temporal extension to SQL2, and solicit members for this working group. The TSQL2 working group design will proceed in the context of the following constraints. * The initial design must be completed by August 23, 1993. * The design will be based on SQL2. In particular, none of the significant extensions envisioned in SQL3 will be assumed to be present. * Initially, the language design will support user-defined time and valid time. Support for transaction time may be added later. * The design will be implementable in the context of conventional relational database technology. In particular, implementations of the the data model and query language constructs will be possible without necessitating major changes to conventional database management systems. * Discrete time will be assumed. * Past and future valid time will be supported. The initial goal of this working group will be to develop a language design to be included in the final workshop report which will be sent to DARPA and to NSF and will be distributed widely to the database and temporal DB user communities. The activities of this working group will be parallel to those of the SQL2/3 and TSQL3 working groups. Interaction in the medium term interaction between these groups will attempt to arrive at consistent approaches. I now solicit those interested in participating in such a language design to join this working group. While participation in this effort will certainly entail significant effort over the next 8 weeks, there is also much to be gained. The resulting language will be the first consensual temporal query language, and as such, will strongly influence TSQL3 and other longer-term query language design efforts. Since this language will be part of the final report, it could very well influence DARPA's activities in temporal databases. This consensual effort will also have visibility with the DBMS vendors, and so could influence temporal support in future commercial products. If you agree with me that a design of an extension to SQL2, in parallel with the longer term design of an extension to SQL3, is an appropriate approach, please let me know. I personally think that the definition of TSQL2 will be a watershed event in temporal database research, and I invite you to join in this effort.