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From Kim Haase <Camilla.Ha...@Sun.COM>
Subject Re: [jira] Commented: (DERBY-2060) SET CURRENT ISOLATION in ref.man refers java.sql.Connection.setTransactionLevel instead of java.sql.Connection.setTransactionIsolation
Date Thu, 30 Nov 2006 16:21:41 GMT
Thank you very much, Bernt -- I appreciate the clarifications.

I will document the current behavior now, and leave you to file an issue 
to describe the needed changes. It sounds as if, among other things, the 
statement needs a new name: SET TRANSACTION ISOLATION.

Kim

Bernt M. Johnsen wrote:
>>>>>>>>>>>>> Kim Haase wrote (2006-11-29 11:31:52):
>> Do you mean SET ISOLATION rather than SET TRANSACTION? (I don't have 
>> access to the SQL 2003 standard.)
> 
> According to the SQL standard, the syntax should be SET TRANSACTION
> ISOLATION...
> 
> In Derby this is implemented as SET CURRENT ISOLATION.....
> 
>> It seems that we have two issues here.
>>
>> 1) The desired change in SET ISOLATION behavior should be in a separate 
>> bug -- maybe DERBY-2064, which is not a documentation bug and where it 
>> is not clear right now what the needed change is, or maybe a new bug 
>> with the broader change.
> 
> Yes. Actually we have 3 alternatives on this
> 1) Change network client driver behaviour to be like the embedded
>    driver ,
> 2) change embedded driver behaviour to be like the client driver, or
> 3) change Derby to be compliant with the SQL standard
> 
> I prefer 3.
> 
>> 2) Should we document the current behavior in the meantime, while 
>> waiting for the fixes? 
> 
> Yes, I think so.
> 
>> If so, what exactly is the current behavior? This 
>> is my understanding -- please correct as necessary:
>>
>> If there is an active transaction, the network client driver always 
>> commits the active transaction if either SET ISOLATION or 
>> Connection.setTransactionIsolation is called. It does this even if the 
>> statement or method call does not actually change the isolation level 
>> (that is, if it sets the isolation level to its current value). The 
>> embedded driver also always commits the active transaction if SET 
>> ISOLATION is called. However, if Connection.setTransactionIsolation is 
>> called, the embedded driver commits the active transaction only if the 
>> call to Connection.setTransactionIsolation actually changes the 
>> isolation level.
> 
> 
> That is my understanding of the current sematics.
> 


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