Re: Question about Append hint in Insert

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Wed, 23 Jun 2004 10:59:59 +0100
Message-ID: <01c001c45908$d7f5d800$7102a8c0@Primary>

Minor detail - but there is one byte per row difference, as the non-unique index stores the rowid as a column entry, which requires a length byte. The unique index stores it as a fixed size payload, which is described once per block (and ought to be described once per index !)

Regards

Jonathan Lewis

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Original Message ----- From: "Lex de Haan" <lex.de.haan_at_naturaljoin.nl> To: <oracle-l_at_freelists.org> Sent: Monday, June 21, 2004 9:21 AM Subject: RE: Question about Append hint in Insert

one small correction: non-unique indexes do *not* allocate more space... both unique and non-unique indexes contain ROWID values, obviously. the difference is that the ROWID values are part of the key value for non-unique indexes,
and they are part of the entry header for unique indexes. Cheers,
Lex.

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Received on Wed Jun 23 2004 - 04:56:47 CDT