snapshot and cursor

Hi,

What I am wondering is if Oracle needs to retain fetched rows of a
snapshot
for read consistency.

Seems to me, the fetched rows cannot be reused, and therefore can be
realeased
from undo space if they've modified and commited.

But I think Oracle still wants to keep these in undo space, and give
snapshot too old
error when they are pushed out.

Thank you for your help.
seinbert

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