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From:Jerry Schwartz Date:June 17 2011 2:11pm
Subject:RE: optimization strategies based on file-level storage
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>-----Original Message-----
<snip>

>What I was really trying to figure out was why it takes me 4 hours to
>add a new column to my 22-million-row table, and whether a different
>table design can avoid that problem.  That reply in the forum says,
>"ALTER TABLE ... ADD COLUMN will always copy the entire table over,
>and rebuild all the indexes. (And, effectively, do an OPTIMIZE.) Do
>_not_ leave space for extra columns, it won't help."  I'm about to
>reply and point out the trick that you suggested to me: create dummy
>columns early and then just rename them later :)
>
>         -Bennett
>
[JS] They will be too small, or the wrong type, or there won't be enough of 
them. Based upon 30+ years of database design, I'd bet money on it. ;-)

Regards,

Jerry Schwartz
Global Information Incorporated
195 Farmington Ave.
Farmington, CT 06032

860.674.8796 / FAX: 860.674.8341
E-mail: jerry@stripped
Web site: www.the-infoshop.com






Thread
optimization strategies based on file-level storageBennett Haselton14 Jun
RE: optimization strategies based on file-level storageBennett Haselton14 Jun
  • Re: optimization strategies based on file-level storageJohan De Meersman14 Jun
    • Re: optimization strategies based on file-level storageBennett Haselton15 Jun
      • Re: optimization strategies based on file-level storageJohan De Meersman17 Jun
        • Re: optimization strategies based on file-level storageBennett Haselton17 Jun
          • RE: optimization strategies based on file-level storageJerry Schwartz17 Jun
            • RE: optimization strategies based on file-level storageWm Mussatto17 Jun