Re: DB2 HADB

"DA Morgan" <damorgan_at_psoug.org> wrote in message news:1132967521.612633_at_yasure...
>
> I'd be really happy to explain it to you if it were true: It is not.
>
> IOTs are very commonly used in Oracle installations and Tom Kyte, in his
> presentations has been featuring them and their value as a way of
> enhancing performance over heap tables for many purposes.
>
> And quite a few organizations I work with use IOTs with partitioning but
> then you wouldn't know about that as DB2 doesn't have partitioning
> capabilities.
>
> Listening to someone who is an IBM DB2 user pontificate about the usage
> of a product he doesn't know would be laughable were it not for the
> fact that some poor soul might actually believe your trolling.
> --
> Daniel A. Morgan

While I certainly use DB2 more than Oracle, I do use Oracle.

I don't really want to argue about how often IOT's are used compared to table clustering in DB2, but I can absolutely guarantee you that DB2 table clustering is used more often. On DB2 for z/OS (which you claim to know about) clustering is the default even if not explicitly defined (using the sequence of the first index created), so pretty close to 100% of tables in DB2 for z/OS use table clustering.

The reason I mentioned table clustering in DB2 was to answer Noon's question about why table reorgs are a much bigger concern in DB2 than Oracle. The reason is because of DB2 table clustering, which needs periodic reorgs for tables with frequent inserts. Received on Fri Nov 25 2005 - 19:43:50 CST