Re: Partitioning tables in Oracle8

>
> There is no automatic creation of indexes.
>
> If you want a unique/PK index on the table it has
> to be either a global (i.e. cross-partition) index or
> it has to start with the partitioning columns - Apart
> from this there is no need to have an index on the
> partitioning column at all.

So if there is no index on the table,
an insert would cause full table scan?
Otherwise how would Oracle know what partition should the new row go into?

>
> Performance can be dramatically improved if your
> partition is correctly selected.
>

I understand it is very beneficial for selects. How about inserts, updates and deletes?
How many additional constraints are imposed on the table/partitions and how would it slow down inserts and updates?

> A suggestion for analyzing if (do you really need to
> do it every night ?) is to analyze the partitions
> separately, not the table as a whole: the only
> time to analyze the table is when you initially
> create it with empty partitions.
>

I am sorry, I used the wrong word!
I mean a long query which extracts the useful data and puts them into other tables and
deletes unusable data.

Thank you!

Misha.

-----== Posted via Deja News, The Leader in Internet Discussion ==----- http://www.dejanews.com/ Now offering spam-free web-based newsreading Received on Sat May 30 1998 - 21:31:25 CDT