RE: Table with 300 columns (ie > 255) : Row Chaining ?
From: Hemant K Chitale <hkchital_at_singnet.com.sg>
Date: Mon, 26 Oct 2009 23:52:47 +0800
Message-Id: <200910261552.n9QFqqF7007609_at_smtp14.singnet.com.sg>
Date: Mon, 26 Oct 2009 23:52:47 +0800
Message-Id: <200910261552.n9QFqqF7007609_at_smtp14.singnet.com.sg>
Some (more ?) surprising
results at
http://hemantoracledba.blogspot.com/2009/10/some-more-testing-on-intra-block-row.html
And I haven't started with tables with more than, say, 512 columns.
Furthermore, I haven't yet obtained statistics on DML impact on redo sizes, as Timothy has pointed out.
These tests are out of what I found as unconvincing performance
statistics when comparing queries on large (>400 columns) FACT Tables
-- eg queries that are aggregates against single columns of the table.
Hemant K Chitale
http://hemantoracledba.blogspot.com
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Received on Mon Oct 26 2009 - 10:52:47 CDT