On Jul 2, 2011, at 2:50 AM, Jason Smith wrote: > On Fri, Jul 1, 2011 at 10:23 PM, Jens Alfke <[email protected]> wrote: >> >> On Jun 30, 2011, at 11:37 PM, Zdravko Gligic wrote: >> >>> But neither one even bothered trying to answer my question of whether >>> just the last updated header or perhaps the last few are ever used. >> >> Just the last one. But at any point in time, the last one is vital for >> recovery. It just becomes useless after another one is successfully appended. > > Isn't that what I said? :) > > The evidence indicates "no." That's a shame. In my daily life I always > worry about starting from an accidental advantage (speaking English), > and assuming everybody else is advantaged, ultimately only causing > confusion. In other words: Most Americans talk too fast, with too much > slang. > > Anyway, to right my wrong and make it clear: > > The bottom rung of a ladder *was* important, when you stepped on it. > Once at the top, we do not care about the bottom rungs.
Well it's important on the way down too :) > > Similarly, the food you ate last year kept you alive, so it *was* very > important. But today, last year's food is not relevant. > > With CouchDB (as others said), the last header is the important one; > but once a new one is written, the old header is not relevant. > > (They might be *slightly* relevant in rare cases. For example, if your > tape media was damaged and you have a partial backup; the old headers, > now at the "end" of the truncated .couch file, are once again useful > to access the older data. That situation however is very unlikely > and/or completely contrived.) > > -- > Iris Couch
