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From chongqing xiao <cqx...@gmail.com>
Subject Re: question about how write_header works
Date Thu, 23 Sep 2010 03:51:57 GMT
Hi, Adam:

Thanks for the answer.

If that is how it works, that seems create a lot of wasted space
assuming a new header has to be appended each time new data is saved.

Also, assuming here is the data layout

newData1   ->start
header1
newData2
header2      -> end

If header 2 is partially written, I am assuming newData will also be
discarded. If that is the case, I am assuming there is a special flag
in header 1 so the code can skip newData2 and find header1?

I am very interested in couchdb and I think it might be a very good
choice for archiving relational data with some minor changes.

Thanks
Chong

On Wed, Sep 22, 2010 at 10:36 PM, Adam Kocoloski <kocolosk@apache.org> wrote:
> Hi Chong, that's exactly right.  Regards,
>
> Adam
>
> On Sep 22, 2010, at 10:18 PM, chongqing xiao wrote:
>
>> Hi,
>>
>> Could anyone explain how write_header (or header) in works in couchdb?
>>
>> When appending new header, I am assuming the new header will be
>> appended to the end of the DB file and the old header will be kept
>> around?
>>
>> If that is the case, what will happen if the header is partially
>> written? I am assuming the code will loop back and find the previous
>> old header and recover from there?
>>
>> Thanks
>>
>> Chong
>
>

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