Thank you for the answer. I though it is possible to compare two _rev fields of two documents and based on the hash part (not the integer) to tell if they have the same content. I guess it is not possible.
Ido On Sun, Sep 12, 2010 at 3:14 PM, Sebastian Cohnen < [email protected]> wrote: > Hi Ido, > > consider the _rev token as an opaque value necessary for the mvcc (I'd call > it mvcc-token, since "revision" is often misunderstood). The hash algorithm > may even change someday. AFAIK it contains the document itself and also its > history (at least parts of it). The algorithm ensures that the same document > with the same history result in the same _rev token even on two different > nodes. This behavior is required for conflict detection/resolution. > > Best > > Sebastian > > > On 12.09.2010, at 14:43, Ido Ran wrote: > > > Hi, > > I've read that the _rev fiel in each document is composed of two parts - > > integer which increment by 1 on each change and MD5 hash of the JSON of > the > > document. > > What part of the JSON is included in that hash? > > > > I've created a new document with _id of "foo" and single field name > "start" > > with value "99". I've save the document and it got _rev of > > "1-b563730fcffb6583ff48980c1533e439". > > I didn't change anything, just hit save again in Futon and not the _rev > is > > "2-75a41bb3bc74cb4d768466efa2a0c1ca". > > If I hit save again I get another hash. > > > > Why is that? > > > > Thank you, > > Ido > >
