Re: Retrieving records in order they were placed.

using just the date is very risky b/c some sys admin will surely reset the clock and then the records will be out of order...

use a non-wrapping sequence into a NUMBER field...

randy

b_rich2_at_my-deja.com wrote:

> I have to put records into a table, and later retrieve them in the order
> in which they were placed. I have a very very large number of entries to
> be placed in a live system. The records are logs of important events in
> the system.
>
> My first thought was to use the unix time stamp to place as the field to
> order on, but there will probably be many entries entered in rapid
> succession. Thus many entries could be entered at the same time stamp
> interval.
>
> I then though of having a sequence number associated with each record,
> increasing one by one with each record stored. This will work well until
> the sequence numbers begin to wrap. If they are retrieved in order of
> sequence number, and then they wrap, the records entered after the wrap
> (sequences 1,2,3,4 etc) will all of a sudden be pulled out before the
> earlier records with high sequence numbers.
>
> Another idea is to just use the sequence numbers, and re-boot the box
> every few weeks when the sequence numbers get high, but this is really
> unacceptable in the environment where this will be run.
>
> Does anyone know how to get around this problem? Any help would be
> GREATLY appreciated.
>
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Received on Sun Jul 11 1999 - 21:55:59 CDT