Jim Fulton wrote:
Chris Withers wrote:
Jim Fulton wrote:
Even if you did track reads, how would you distinguish an unsafe
read as above from a normal read that shouldn't cause a conflict?
A write (or the undo of a write) would conflict with any reads in later
transactions.
Wouldn't that,
Chris Withers wrote:
Jim Fulton wrote:
Chris Withers wrote:
Jim Fulton wrote:
Even if you did track reads, how would you distinguish an unsafe
read as above from a normal read that shouldn't cause a conflict?
A write (or the undo of a write) would conflict with any reads in later
Chris Withers wrote:
Jim Fulton wrote:
...
Even if you did track reads, how would you distinguish an unsafe read
as above from a normal read that shouldn't cause a conflict?
A write (or the undo of a write) would conflict with any reads in later
transactions.
Jim
--
Jim Fulton
Hi Jim,
Jim Fulton wrote:
BTW, I strongly discourage use of Undo except in emergencies.
Sadly, except when undoing the last (non-undo) transactions in
a database can lead to inconsistency.
What sort of inconsistencies are you referring to?
Undo can be a very attractive feature although
Chris Withers wrote:
Hi Jim,
Jim Fulton wrote:
BTW, I strongly discourage use of Undo except in emergencies.
Sadly, except when undoing the last (non-undo) transactions in
a database can lead to inconsistency.
What sort of inconsistencies are you referring to?
Logical inconsistencies.
On May 17, 2006, at 6:54 AM, Jim Fulton wrote:
It was claimed earlier in this thread, that plone only lets you
undo the
most recent transactions. If this is true, then that should not be
a problem. A facility that let you only undo last transactions
would be safe. It would also be useful,
David Pratt wrote:
There seems to be enough of a difference between Z2 and Z3 undo to have
an effect on a backend like PGStorage from working on Z3. I believe the
objective in the storage api is that it should not matter to the backend
whether you are connected to Z2 or Z3. Can someone more
Jim Fulton wrote:
David Pratt wrote:
There seems to be enough of a difference between Z2 and Z3 undo to
have an effect on a backend like PGStorage from working on Z3. I
believe the objective in the storage api is that it should not matter
to the backend whether you are connected to Z2 or Z3.
Hi Jim. I managed to fix this by modifying the storage but it seems to
me strange to differentiate in a storage whether it is a backend to a z2
or z3 app.
Regards,
David
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