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From Vaide Zuikeviciute <vaide.zuikevici...@gmail.com>
Subject Re: Serializable isolation level
Date Fri, 25 Nov 2005 07:48:16 GMT
Daniel John Debrunner wrote:

>vaide wrote:
>  
>
>>How well Derby handles concurrent clients under Serializable isolation level?
>>Does serializable isolation level enforce sequential execution of transactions
>>even if transactions do not conflict at the row level? 
>>Is there a big chance that TPC-C like transactions will execute sequentially in
>>Derby?
>>    
>>
>
>No, such transactions will proceed concurrently in serializable mode.
>Obviously if they access the same rows they will be serialized.
>  
>
My point was, that since such transactions can accumulate a number of 
row locks, even if single SQL statements woudn't touch enough rows to 
escalate from row level locking to table level locking, Derby might 
choose table-level lock at the end. Is it true also, that if my 
statement scans entire table and then updates only a single row, table 
level lock will be held?
How could I monitor locks from my app.?
Thanks!

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