Alexandre Benson Smith wrote:

>
> Does Oracle use MGA ? (I think it implements something like a log for
> it, don't know how it could be considered MGA)

It provides snapshots for repeatable read but is not natively MGA.

>
>
> Index Organized tables are Clustered Indices ?
> You can have only one clustered index per table, if you store all
> information on the index page (making a clone of the data for each
> clustered index, it will increase a lot on every table modification), I
> think I didn't get it... Could you explain a bit more ?

Databases that store data in indexes - there are lots, it's not a new
idea - I think at least two of the MySQL backends work that way -
generally have secondary indexes that resolve to the primary key of the
record you want. So, if you're looking for the author of a book and the
primary key of the table Books is ISBN and there is a secondary index on
Title, the system uses the title index to retrieve the matching ISBN,
then uses that value to get the record and the author's name.

Regards,


Ann