Re: serialized transactions

Jonathan Lewis a écrit :

> It is possible that you were just lucky on the first test,
> or possibly you have some init.ora setting (such as
> delayed_logging_block_cleanout) set differently.
>

Thanks for the hint. But I have 2 remarks : 1 - That was not luck on a solaris plateforme with Oracle 7.3.3, the scenario as is worked for all the tries taht I did till now. 2 - In all cases I had delayed_logging_block_cleanout set to true

> My guess is that you have INITRANS = 1 on the table.
> For any table in a serialized transaction you need initrans
> set to at least 2 to allow for a different strategy for
> read-consistency (this is documented somewhere, but
> don't ask me where).

Right but strange for me. Normally IINITRANS is set to 1 and "doesn't need to be changed." according to the documentation. On the other hand, I have MAXTRANS set to 255! Someone has more precision on that?

> Mohamad SALEH wrote in message <37049D05.76C12441_at_orsys.fr>...
> >I have a plateforme Solaris 2.6 intel x86. Oracle server 7.3.3.
> >The documentation says that the granularity is on a row level.
> >
> >I simply use two concurrent transactions. Here the instructions I use in
> >chronological order.
> >Column C1 is a primary key, v1, v2 are different values of C1.
> >
> >"Transaction 1"
> >1 - SET TRANSACTION ISOLATION LEVEL SERIALIZED;
> >2 - SELECT * FROM T;
> >
> >"Transaction 2 "
> >3 - UPDATE T SET C2 = ... WHERE C1 = v1;
> >4 - COMMIT;
> >
> >"Transaction 1" : Suite
> >
> >5- SELECT * FROM T;
> >6 - UPDATE T SET C2 = ... WHERE C1 = v2;
> >7 - UPDATE T SET C2 = ... WHERE C1 = v1;
> >
> >In this sequence and on this plateform, I have the message in step 7
> >stating that it is not possible to serialize which is conform to the
> >documentation.
> >
> >But when I add even a SELECT statement on transaction 2, I have the
> >message on the 6th!
> >I made a test on NT with Oracle 7.3.4 and there the message notifying
> >the problem is always on the 6th step
> >even with the sequence described up here.
> >
> >Please repond by E-mail and thanks in advance.
> >
Received on Wed Apr 14 1999 - 08:56:35 CDT