Tom Lane wrote:
> 2. I had first dismissed Neil's idea of transactional sequence updates
> as impossible, but on second look it could be done. Suppose RESTART
> IDENTITY does this for each sequence;
>
> * obtain AccessExclusiveLock;
> * assign a new relfilenode;
> * insert a sequence row with all parameters copied except
> last_value copies start_value;
> * hold AccessExclusiveLock till commit.
Hmm, this kills the idea of moving sequence data to a single
non-transactional catalog :-(
> So what I think we should do is leave the patch there, revise the
> warning per Neil's complaint, and add a TODO item to reimplement RESTART
> IDENTITY transactionally.
I think the TODO item did not make it, but the docs do seem updated.
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