Re: Q:Object query (nested tables?) vs query on normalized tables

Hi Jonathan:

It kind of looked like it was, because the docs talk about "hidden columns", etc. So it isn't necessarily any BETTER performance-wise. What are the odds of it being worse? Can one make indexes on these phantom tables, etc. or if I want to search for credit card transaction data (as in my example) am I doing full table scans left and right?

Thanks,

    Mike

Jonathan Lewis wrote in message
<979068270.22040.1.nnrp-10.9e984b29_at_news.demon.co.uk>...
>
>Nested tables are implemented as normlised tables
>with a meaningless key combined with a hidden
>unique constraint on the parent table, so it's all
>overhead and no (physical) benefit over doing it
>the relational way.
>
>
>--
>Jonathan Lewis
>Yet another Oracle-related web site: http://www.jlcomp.demon.co.uk
>
>Practical Oracle 8i: Building Efficient Databases
>
>Publishers: Addison-Wesley
>See a first review at:
>http://www.ixora.com.au/resources/index.htm#practical_8i
>More reviews at: http://www.jlcomp.demon.co.uk/book_rev.html
>
>
>
>gnn_gnn wrote in message <93ebi5$t56$1_at_nntp9.atl.mindspring.net>...
>>Hi:
>>
>>I have been looking at the documentation on defining types, objects,
 nested
>>tables, etc. in Oracle 8i and have a basic question on the topic as a NB.
>>Some of these things look very interesting, like points, lines, etc. But
>>how does the query speed stack up? For example, if I wanted a list of
>>people and all of their credit card transactions for a month (or several
>>months) and wanted to do queries like "show all the people, and the
>>transactions who spent more than $200 on clothes in the month of
 december".
>>Would I be better off using something like nested tables
 (performance-wise)
>>or breaking out the credit card transactions into a separate table with a
>>foreign key back to the user table? What are the pros and cons of each
>>method?
>>
>>Thanks,
>> Mike
>>
>>
>>
>
>
Received on Tue Jan 09 2001 - 18:06:17 CST