On 02/25/2015 09:40 AM, Igor Tandetnik wrote: > On 2/25/2015 9:16 AM, russ lyttle wrote: >> To eliminate the need to reference a table would require combining 300 >> tables into one table. > > Yes. > >> A user editing entries for one space could crash >> the whole system. > > I don't see how this follows. > >> That's basically what happened aboard the Yorktown in >> 1997. A cook trying to enter an item into the lunch menu killed the >> engines on the ship. > > Did the software store engine configuration and menu in the same table? > Did the software need to run statements joining engine configuration > tables with lunch menu tables, thus necessitating putting them into the > same database? How is scattering essentially the same data across 300 > different tables is expected to help prevent a similar mishap? > >> It's beginning to look like the 'b' table should be broken into a >> separate db and the 'a' table have indicators as to which table in b.db >> to use. > > What failure mode do you envision that would be avoided by this design?
There was a lot of finger pointing about the Yorktown incident. The DB people blaming NT, the Microsoft people blaming the DB. Apparently the cook tried to enter more items in the supper menu than was allowed and caused a cascading failure ending in an engine shutdown. A complete system reboot was required. Whether or not that was due to the DB or OS doesn't matter now. The goal is to prevent similar events. Or at least make it obvious where the fault lies. I was personally involved in one incident where an occupant stuck a soda can in a damper and caused a system shutdown. -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 473 bytes Desc: OpenPGP digital signature URL: <http://mailinglists.sqlite.org/cgi-bin/mailman/private/sqlite-users/attachments/20150225/699f61a0/attachment.pgp>
