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Is there a rule of thumb for creating a tablespace with extent management AUTOALLOCATE or UNIFORM? If the latter applies, how to estimate a reasonable extent size?

Even more, what should apply for default tablespaces like SYSTEM, SYSAUX, UNDO, and TEMP?

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up vote 2 down vote accepted

I agree with Tom Kyte's 2005+ assessment of this:

I actually am a fan of system allocated extents now. It grows the extent allocation size as the table grows.

Autoallocate is not going to cause widespread fragmentation.

IF you know PRECISELY how big the object is, will be or will grow by -- go ahead, do the math, feel free to use uniform. Else, use autoallocate...

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Just another issue. If I do have a broad diversity of objects, I cannot calculate any uniform size. I would always require to have concrete objects in that tablespace. –  Michael-O Jun 5 '12 at 21:31

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