I seem to recall an e-mail storm a few months ago regarding this versioning of database updates, in order to preserve every instance of every record. Maybe I am remembering the wrong discussion. Is this enormously difficult, or a massive storage hog, or can't we just update the object table with the latest and best values?
- Kirk > Date: Fri, 18 Aug 2006 05:42:41 -0700 > From: Tim Axelrod <[EMAIL PROTECTED]> > Subject: Re: [LSST-data] Re: cpu for queries > To: Jacek Becla <[EMAIL PROTECTED]> > Cc: LSST Data Management <[email protected]>, [EMAIL PROTECTED] > > Jacek, > > Ouch! I had forgotten that you wanted to do this. I'm afraid this > makes more than just the alertid proposal unworkable. The whole concept > of having summary information for the object, such as a wavelet > decomposition of its lightcurve or even the mean magnitude, that is > updated as we go along is gone too. Living with this would be very > difficult! What alternatives do we have? > > Tim > > Jacek Becla wrote: > > Kirk, Ani > > > > There is one small complication with keeping the most recent > > alertid for each Object: it requires updating existing rows. > > It would be nice to have the design of largest tables such that > > each row is written one, and kept read-only after that. > > Such approach guarantees reproducibility, and make it more > > manageable (easier to replicate and distribute). > > Changes/updates would be done through versioning, but > > I'm not sure it is worth using versioning in this case. > > > > Jacek > > > > > > _______________________________________________ > LSST-data mailing list > [email protected] > http://www.lsstmail.org/mailman/listinfo/lsst-data ----------------------------------------------------------------------------- Dr. Kirk D. Borne NASA Goddard Space Flight Center, SSDOO Program Manager, QSS Group Inc. and George Mason University, Associate Research Professor, College of Science <mailto:[EMAIL PROTECTED]> Tel. +1-301-286-0696 Fax: 301-286-1771 Staff page: http://rings.gsfc.nasa.gov/~borne/ US Virtual Observatory: http://www.us-vo.org/ Large Synoptic Survey Telescope: http://www.lssto.org/ _______________________________________________ LSST-data mailing list [email protected] http://www.lsstmail.org/mailman/listinfo/lsst-data
