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From frederic barachant <ms.barach...@free.fr>
Subject Re: commit then read immediately
Date Wed, 18 Apr 2007 16:12:30 GMT
Bryan Pendleton a écrit :
>> Initialisation consists in writing objects through jpa. After commit 
>> is done, the program starts and reads back those data.
>
> I haven't heard of any problems involving a delay after commit in Derby
> itself. Perhaps jpa is not committing the data when you think it is, or
> perhaps your program is starting too soon?
>
The two parts of the program are executed one after the other, so there 
can be no read before write and even if there would be a possibility for 
the two (netbeans modules) to be swapped, it would hang. First module 
starts a socket after db is initialised and second module can only get 
the data through that socket. (in case you wonder why, multiple machines 
can access that data, so i only implemented socket to reduce code and 
hopefully problems. That access is not a bottleneck. )
I just double-double checked that there were no read access to the data 
before write.
> Is this one program or two? Are there multiple threads involved? What is
> your transaction isolation level?
>
This is a netbeans module suite, database is filled during startup using 
their startup hooks.
The data is accessed seconds later from the AWT thread when i try to 
display them in a TreeView (thus in AWT thread, thus an other one).

Transaction is the default one, so i guess from documentation it is 
/TRANSACTION_READ_COMMITTED.

/

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