Re: snapshot

Hello Ercih,
we had the same problem last week!
All is due to the sys.slog$ located on master database (which snapshot log) This table maintains theoricaly 1 row for each snapshot with the last refresh time indication.
(if you have 2 snapshots for the same master table, ie with 2 different dblink, you will have 2 rows in slog$)
Two known cases :

1. slog$ not empty : If there is too many or less rows in slog$ than real snapshots then fast refresh cannot be used. In some case (network failure, break during refresh processing, long unaivalability connection between master and snapshot db,....) you can have a row more for a snapshot in slog$ and so no fast refresh can be done. In this case (not same count of snapshot and rows in slog$) you have 2 solutions to solve it : - drop the identified snapshots then the associated snapshot log and recreate snapshot log and snapshot It's a little bit hard but it works. - More soft, you can use dbms_snapshot.purge_log (or dbms_refresh.purge_log, I don't remember well) to reajust the slog$. (see Server Distributed Systems, Vol 2replicated
2. slog$ empty : But another problem can be the cause of your "no refresh fast" : a compilation problem with some packages of replication (installed with catrep.sql script). In this case sys.slog$ is completly empty. So you could recreate all snapshots and snapshot log, the problem will remain. To solve it, you have to re-install catrep. That's what happened for us and now all works fine. And before this, don't forget to backup and save (with exp) your db!

Hope this help you
BR
Olivier

"Erich" <ese_at_ozemail.com.au> a écrit dans le message news: SpKy4.45642$3b6.195203_at_ozemail.com.au...
> Using Oracle 7.3.4, created a snapshot between to databases on different
> servers (NT4). Created the snapshot with fast refresh. Also created
 snapshot
> log on the master table.
>
> When trying to refesh, get the following error message:
>
> ERROR at line 1:
> ORA-12004: REFRESH FAST cannot be used
> ORA-06512: at "SYS.DBMS_SNAPSHOT", line 271
> ORA-06512: at "SYS.DBMS_SNAPSHOT", line 139
> ORA-06512: at line 1
>
> If I change to "refresh complete" everything works. The snapshot is a very
> simple one, using a trial database with only a few records.
>
> Any suggestions would be appreciated.
>
> Erich
>
>
Received on Tue Mar 14 2000 - 00:00:00 CST