Re: Distributed systems and primary keys

On Fri, Jul 12, 2013 at 9:46 AM, Joshua D. Drake <jd(at)commandprompt(dot)com>wrote:

>
> On 07/12/2013 07:23 AM, Melvin Call wrote:
>
>> Hello list,
>>
>> Can anyone point me to some reading material on how auto-generated
>> sequence primary keys are handled on distributed systems? I think the
>> advice used to be to use GUIDs, but I thought I read somewhere that
>> PostgreSQL now assigns a pool of numbers to each node when a sequence is
>> implemented. I have searched the PostgreSQL 9.1.5 Documentation, but
>> apparently my search terms are not quite what it takes, or dreamt that up.
>>
>
> PostgreSQL itself does not support a distributed architecture. You may be
> thinking of Postgres-XC?
>
> Sequences are local to each instances and it is not a pool, it is a 64bit
> allocation for each sequence within the local node, generally constrained
> only when called from the serial (big serial being 64 bits) type to 32 bits.
>
> Sincerely,
>
> Joshua D. Drake
>

Thank you Joshua.

Yep, if you are correct, and I believe you are, then obviously I was
thinking of something else (this happens when you work on multiple systems
I'm afraid). That would explain why I was having so much trouble finding
something that wasn't there.

This will make our planning a bit easier because I now know what the limits
currently are. I will be checking out Postgres-XC as well.

Regards,
Melvin