[OAI-implementers] new records in combination with a resumptionToken

deridder deridder@cs.utk.edu
Fri, 25 May 2001 12:42:15 -0400 (EDT)

Hi Josef!

  My resumption tokens include a number which specifies how many entries 
of a set have been already offered;  I simply skip that many on the next 
output, print my chosen number (20), and adjust the resumption token

  Since I'm simply printing out a certain number of entries rather than
specific file numbers, this works regardless of having added or deleted
database entries.

   I know, simplistic, but it works.  I belong to the KISS followers!

Wed, 23 May 2001, Jozef Kruger wrote:

> Hello everybody,
> when implementing the resumptionToken-stuff, the following problem arose:
> Our database has a function startfrom-limit(n, m) which starts at the n'th
> record and get's m records.
> It ignores the first (n-1) records, the records are ordered by record
> number.
> When ListRecords is called, I return the first 10 records in my database
> (with recordnumbers 1..6, 8..11), followed by a resumptionToken.
> As follows: startfrom-limit(1, 10);
> The next second a record is added to the database and it get's record number
> 7 (the lowest free record number).
> When the resumptionToken is used, I return the records 11-20 in my database,
> as follows: startfrom-limit(11, 10);
> but having added the record number 7, the record with record number 11 will
> be return twice.
> Is it necessary to explicitly avoid this behaviour? I ask this because I
> think this situation is quite rare (or am I wrong?).
> thanks in advance :)
> cheers,
> Jozef Kruger
> -----------------------------------------------
> Jozef Kruger, junior programmer.
>     Adlib Information Systems
>      www.adlibsoft.com <http://www.adlibsoft.com> 
> -----------------------------------------------

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