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Home -> Community -> Mailing Lists -> Oracle-L -> Re: Local Prefix vs non-prefix indexes
Hi, Frank,
You seem to conclude the opposite of what Rick has read. Not only that, but I
also suspect you're confusing local non-prefixed indexes with global indexes.
Consider me as a newbie. My understanding is that a local index, prefixed or
not, is always equipartitioned with their table partition. I.e. one local index
partition always contains rowids of the data in its own table partition. Look
at Figure 11-5 at
http://technet.oracle.com/docs/products/oracle8i/doc_library/817_doc/server.817/a76965/c09parti.htm.
Note that ranges of ACCTNO's are not sequential when you move from left to
right, as are DEPTNO (the table partition key). The triangles representing
indexes are an excellent example of illustration in that they *are*
self-contained B-tree indexes in their own right.
It's true that "In a non-eqiupartitioned environment a change to the table might invalidate all of the index partitions", which sounds like global indexes.
But I can't give an answer to Rick's question. What book is it, Rick? By whom? On what page?
Yong Huang
yong321_at_yahoo.com
you wrote:
Rick:
Local prefixed indexes are equipartitioned with the table. Therefore if I do some maintenance on the table partition it invalidates the corresponding index partition but only that one. The index partition then needs to be rebuilt. In a non-eqiupartitioned environment a change to the table might invalidate all of the index partitions.
Frank Marshall
----- Original Message -----
From: "Cale, Rick T (Richard)" <RICHARD.T.CALE_at_saic.com>
To: <oracledba_at_lazydba.com>; <ORACLE-L_at_fatcity.com>
Sent: Wednesday, November 29, 2000 7:03 AM
Subject: Local Prefix vs non-prefix indexes
> I was reading about partitioning and it states the following:
>
> "Local nonprefixed indexes provide more availability than prefixed indexes
> when partition maintenance operations are carried out."
>
> Can someone explain WHY?
>
> Thanks
> Rick Cale, Science Applications International Corp.
> Phone:865-481-2198, fax:865-481-8555
> e-mail: caler_at_saic.com
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