Hello Andreas, cordial thanks for the additional information. To summarize my understanding: a feasible way to effect a "rolling database" which is periodically renamed and replaced by a newly created database is feasible in a multi-client environment - when one provides a "manager client" triggering theses actions. I shall gladly come back for more information should the need arise.

Cheers,

Hans-Juergen

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Von: Andreas Weiler <andreas.weiler@uni-konstanz.de>
An: Hans-Juergen Rennau <hrennau@yahoo.de>
CC: Base X <basex-talk@mailman.uni-konstanz.de>
Gesendet: 8:57 Donnerstag, 5.Juli 2012
Betreff: Re: [basex-talk] BaseX as a log msg store?

Hello Hans-Juergen,

was this database renaming+creation triggered by the client or autonomously done by the server?

I have a kind of "manager" client running, which executes the database renaming+creation for each hour. Since we have 

single writer transactions, all other transactions are blocked during that time. So the next client transactions will automatically

use the "new" database.

I have it running like this:

create db tmp <root/>

.... insert items ....

close

alter db tmp date_hour

create db tmp <root/>

..... insert items ....

Concerning the querying tasks to be expected I know very little myself - except for the need to group messages by transaction IDs and then somehow evaluate the execution of transactions. But at the moment I suppose that your "monster document" approach might be appropriate in our case, too.

I guess a "monster document" will be fine. However i would not create too large database, cause you probably need to create indexes afterwards and that could take a long time for *very* large databases.

Let me know if you need more information,

Andreas