>>In this case exactly. You wrote about read >>committed transactions so I
>>made such notation)
ok, yes i have wroted i simplified example about read commited but here snapsot
is vital
>>One more note about your idea. Engine >>will have to read every record
>>in anycase. But maybe expression
ср, 25 июл. 2018 г. в 13:08, liviuslivius :
>
>
> > Note: this SELECT may have greater CN then you have stored and it
> > means on the next step you may receive records already selected here.
> > You merge algorithm should take it into account.
> >
> > Roman Simakov
>
>
> If transaction is in
> Note: this SELECT may have greater CN then you have stored and it
> means on the next step you may receive records already selected here.
> You merge algorithm should take it into account.
>
> Roman Simakov
If transaction is in snapshot isolation mode then problem should not exists
Firebird
ср, 25 июл. 2018 г. в 10:38, liviuslivius :
> but from below scenario you can bring the idea
>
> usage case:
> 1.
> TR1 insert and update data on TableX and is still active
>
> 2.
> Application do
> TR2 start and we get recentCN and remember it as interestingCN
> and we do
> SELECT *
>I don't know if IB's "Change View" really useful feature. Do you have some
> expirience\opinon?
>
> Regards,
> Vlad
Sadly, no.
We have had too many problems with Interbase stability and the worst ever seen
paid support (Fortunately, Delphi support works well),
that we have not tried to
24.07.2018 11:13, liviuslivius wrote:
Hi,
question about this patch
https://github.com/FirebirdSQL/firebird/pull/105
Is this possible that this CN(commit number) of transactions (pair transaction
id + CN) can be stored into some table?
Currently - no. Probably we could find a way for it.
вт, 24 июл. 2018 г. в 17:06, liviuslivius :
> Is this possible that this CN(commit number) of transactions (pair
> transaction id + CN) can be stored into some table?
CN is not stored at all. A list of CommitNumbers is generated looking
into TIP on database init in memory. Then it's mainainted
Ok, the name is not so important but call it recentCN
but extended sample
--
Is this possible that this CN(commit number) of transactions (pair transaction
id + CN) can be stored into some table?
Is it possible to retrive most recent CN from transaction start point
24.07.2018 13:43, Mark Rotteveel wrote:
The term SCN is already used by nbackup, lets not muddle the waters by overloading it for
another usecase.
Taking into account usage of "SCN" term in Oracle, it is better to invent a new one for
nbackup than for transaction-related counter.
--
> > you do
> > SELECT * from tableX where RDB$RECORD_VERSION>2
> >
> > above select will not see data commited by transaction id=1 because
> > it modify records before tr2 start
> > and tr1 is commited after tr2 start
>
> :) tr1 committed BEFORE select in tr2 and in read committed mode MUST
>
On 2018-07-24 10:13, liviuslivius wrote:
Hi,
question about this patch
https://github.com/FirebirdSQL/firebird/pull/105
Is this possible that this CN(commit number) of transactions (pair
transaction id + CN) can be stored into some table?
Is it possible to retrive most recent CN from
вт, 24 июл. 2018 г. в 13:15, liviuslivius :
>
> Hi,
>
> this is not the same
> consider:
>
> transaction id=1 exists and is not commited but have modified some records in
> tableX.
> you start new transaction id=2 (read commited isolation mode)
> you commit transaction id=1
>
>
> you do
> SELECT
Hi,
this is not the same
consider:
transaction id=1 exists and is not commited but have modified some records in
tableX.
you start new transaction id=2 (read commited isolation mode)
you commit transaction id=1
you do
SELECT * from tableX where RDB$RECORD_VERSION>2
above select will not see
24.07.2018 10:13, liviuslivius wrote:
It can provide simple way to retrive new records/changes in tables (new
feature).
E.g. whe can then do
SELECT * FROM TABLEX WHERE CN>:SCN;
You already can do it with RDB$RECORD_VERSION.
--
WBR, SD.
Hi,
question about this patch
https://github.com/FirebirdSQL/firebird/pull/105
Is this possible that this CN(commit number) of transactions (pair transaction
id + CN) can be stored into some table?
Is it possible to retrive most recent CN from transaction start point (call
this SCN).
It can
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