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Date: Fri, 28 Sep 2012 09:51:02 -0700
From: Rick Hillegas <rick.hillegas@oracle.com>
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To: derby-user@db.apache.org
Subject: Re: CURRENTVALUE is not "as expected"
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On 9/28/12 9:36 AM, Daniel Butler wrote:
> Hi there,
>
> I was trying to access/use:
>
> SELECT CURRENTVALUE FROM SYS.SYSSEQUENCES WHERE SEQUENCENAME='SOMETHING'
>
> It appears not to return the expected value, in fact it seem to add 5 
> to the expected value or some other number but not what is expected.
>
> Surely this cannot be considered correct/reasonable ?
> Is there any way to access the real CURRENTVALUE (I don't think 
> (CURRENTVALUE-X) is a good solution, since it is not clear what X 
> should be at any one time)
>
> Thanks,
> Daniel Butler.
Hi Daniel,

Directly selecting from sys.sysequences will cause concurrency problems 
for your application. Probably what you want to do is call the builtin 
function SYSCS_UTIL.SYSCS_PEEK_AT_SEQUENCE. The behavior you are seeing 
is explained by the Derby Reference Guide in the section titled 
"SYSCS_UTIL.SYSCS_PEEK_AT_SEQUENCE system function".

Hope this helps,
-Rick