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Old 09-27-05, 02:54
mohdsaid mohdsaid is offline
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Question table fragment

Hi All,
Need to fragment the table for performance reason. What should I do with the index. Should I detach it first then followed by table fragment? or may be any other ways to do it ?
How could I do reindex the table after the table was fragmented?
Thank you very much.
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Old 09-27-05, 08:21
gurey gurey is offline
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Hi,

I suggest that save the schema of the table, next drop all index, next run ALTER FRAGMENT ON TABLE xxxxx INIT IN FRAGMENT BY [expression | round robin] IN dbspace list. Next create index. This indexes will be fragmented as table.

Gustavo.
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Old 09-28-05, 23:41
mohdsaid mohdsaid is offline
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Hi Gustavo,
Q1- How to estimate the dbspace list ? How big for each dbspace should be ? should I base on the table size and and divide by the dbspace list and allocate the size accordingly or few Gb extra ?

Q2- Is the table size is still limit to 64 Gb once the table was fragmented ??
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Old 09-29-05, 06:59
matute matute is offline
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Q2: The table limit will be aprox 16MillionPages per fragment.

Q1: It depends. I usually recomend to create 1 fragment per different 'logical' disk - if you have a disk cabinet, RAID or someting like it makes 1 big disk -> create all the dbspaces you like.
The extent sizes you use are the fragment extent sizes:
extent size 100 next size 50: every fragment will be 100Kb when created.

About the dbspaces size: divide and take an extra Gb - say 2x36, or 4x20, or 8x10... but take care about the fragment expressions.

BTW: it would be nice to have the table schema (use the -ss option for dbschema) and know which columns your apps use most.
__________________
José Luis Matute.

Regards from Spain.
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Old 09-29-05, 11:33
blackguard blackguard is offline
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It is not the 64 GB table limit that you've reached but the 16,777,715 pages per table fragment limit. When you fragment your database, each dbspace is a fragment, hence 2 dbspaces = 2 fragments, and total pages will be 2 * 16,777,715 pages.

On you Q1: I'm sure you can figure that out.
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