Re: One Big Extent vs Multiple Extents

In article <brosalesCz9unG.Er8_at_netcom.com>, brosales_at_netcom.com (Bob Rosales) says:
>But now with striping, is there advantage to
>[create a single extent] at all? I have heard that actually multiple
>extents are better? Can some one suggest any
>paper or your thoughts on this issues?

oracle must perform recursive sql to locate a next extent when inserting new data, so one extent big enuf for inserts avoids this overhead. if the table is query-only or query-mostly, lots of extents present little extra overhead, relative to a full table scan of large extents. in the world of parallel loading, you cannot avoid multiple extents, period. and to take advantage of striped tablespaces, you want multiple extents.

there is an article about tablespace fragmentation which discusses multiple extent overhead in this month's ORACLE magazine. the author concludes that it's not a big deal in today's world.

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Dave Mausner, Sr. Consultant, Braun Technology Group, Chicago.