Re: defragmentation and Oracle v7...automagic??

In article <mike.41.02CAC96D_at_conant.com>, mike_at_conant.com (Michael V. Conant) writes:
> Sorry for the novice question, but I can't get an answer in my perusal of the
> manuals....
>
> The Oracle FAQ mentions that v7 "automagically" defragments tables. To what
> extent is this true? (no pun intended).
>
> Are extents defragg'ed in a segment,

No.

> or is this referring to block chaining issues ?

Block chaining issues are still only fixed by EXP/IMP or you could use ANALYZE to find out which row is chained and simply drop and reinsert the row again. Actually, 'simple' is not a good word to use when discussing chaining.

> Does this "feature" eliminate the need for database export/import efforts?

No.

Oracle7 defragments tablespaces. Actually, all it does is, if it finds two or more adjacent unused fragments it simply combines them into one fragment. It does NOT move database objects (tables, indexes, etc) around to combine all unused space into a single fragment.

I think SMON is the background process that wakes up and checks for fragments.

-- 

Bruce...        pihlab_at_cbr.hhcs.gov.au

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* Bruce Pihlamae  --  Database Administration                     *
* Commonwealth Department of Human Services and Health            *
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