Re: Sequencing Problem in Transaction..

Bhuvan A wrote:
> 
> 
> On Feb 12, Christopher Kings-Lynne wrote:
> 
> > Ummm...this is not a bug - it is utterly essential that sequences are not
> > rolled back!!!
> > 
> > Think about this:
> > 
> > Sequence counter is 9
> > Transaction 1 gets sequence no. 10
> > Transaction 2 gets sequence no. 11
> > transaction 1 rolls back, sequence no. reset to 9
> > Transaction 3 gets sequence number 10
> > Transaction 4 gets sequence number 11 - BAM!!!
> > 
>     Good and Thankx!!!

Believe it or not, this _wasn't_ in the FAQ, though it certainly is
asked enough times.  Added now as item 4.15.4:
  4.15.4) Why aren't my sequence numbers reused on transaction abort? Why are  there gaps in the numbering of my
sequence/SERIALcolumn?     To improve concurrency, sequence values are given out to running  transactions as needed and
arenot locked until the transaction  completes. This causes gaps in numbering from aborted transactions.
 

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