Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Mailing Lists -> Oracle-L -> Re: Asynchonous CDC in 10GR2

Re: Asynchonous CDC in 10GR2

From: Arul Ramachandran <contactarul_at_gmail.com>
Date: Fri, 9 Jun 2006 11:02:02 -0700
Message-ID: <1c1a62990606091102v21822ad8w5b4a83733f7ca200@mail.gmail.com>


David,

Yes, I noticed that yesterday. I wish it was based on range partitioning on TIMESTAMP$, so I can have monthly partitions (that way I can do exchange partition). No luck:( ..... I probably can achieve this by defining multiple CHANGE SETs for a month using the begin_date, end_date - except that it will still be partitioned on CSCN$. Any comments on this?

I tried dropping the change table using 'drop table ..', so that I can re-create it as range partitioned on TIMESTAMP$. But Oracle would not allow that, as the table can be dropped only via DBMS_CDC_PUBLISH.DROP_CHANGE_TABLE.
>>1. After letting dbms_cdc_publish.create_change_table create the change
table, is it ok to (manually) add columns to it? I need to >>add a couple of snapshot columns that are not present in the base table.

>>2. Would it be possible to implement a database insert trigger on the
change table to populate the snapshot columns of the change >>table?

I could add columns to the table. I also added a before insert trigger , the trigger compiled fine, but would not execute. I knew this is the behavior in Streams, same goes here as well. I believe the normal database triggers won't work in this situation ...if you have any ideas, that would be great.

Thanks,

Arul

On 6/8/06, David Lord <davidclord_at_fastmail.co.uk> wrote:
>
> Arul,
>
> The change tables are partitioned on a high value of the CSCN$. As to
> adding columns, everything I can see suggests that the change tables are
> perfectly normal, there doesn't appear to be any 'magic' going on. In
> fact, when I logged a TAR for a performance problem with a query on a
> change table, Oracle support suggested that it was okay to add indexes
> to them (I ran into problems when I did because the purge job marked the
> indexes as unusable).
>
> Regards
> David
>
> On Wed, 7 Jun 2006 10:42:52 -0700, "Arul Ramachandran"
> <contactarul_at_gmail.com> said:
> > David,
> >
> > Thanks for your reply.
> >
> > I am aware of the ALTER_CHANGE_TABLE, but my intention is to add columns
> > to
> > the change table that are not present in the source table. Hence, I was
> > wondering if I could manually alter the change table.
> >
> > Regarding, partitioning of change table, I see from your comment CDC
> does
> > partition it (probably a max val partition?).
> >
> > I don't have my environment yet, otherwise I can check out.
> >
> > Regards,
> > Arul
> --
> David Lord
> davidclord_at_fastmail.co.uk
>
> --
> http://www.fastmail.fm - Or how I learned to stop worrying and
> love email again
>
>

-- 
Arul

--
http://www.freelists.org/webpage/oracle-l
Received on Fri Jun 09 2006 - 13:02:02 CDT

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US