Hi,
On 2015-06-25 PM 01:01, Michael Paquier wrote:
> On Thu, Jun 25, 2015 at 12:57 PM, Fujii Masao wrote:
>> On Thu, Jun 25, 2015 at 12:15 PM, Michael Paquier wrote:
>>> and that's actually equivalent to that in
>>> the grammar: 1(AAA,BBB,CCC).
>>
>> I don't think that they are the same. In the case of 1(AAA,BBB,CCC), while
>> two servers AAA and BBB are running, the master server may return a success
>> of the transaction to the client just after it receives the ACK from BBB.
>> OTOH, in the case of AAA,BBB, that never happens. The master must wait for
>> the ACK from AAA to arrive before completing the transaction. And then,
>> if AAA goes down, BBB should become synchronous standby.
>
> Ah. Right. I missed your point, that's a bad day... We could have
> multiple separators to define group types then:
> - "()" where the order of acknowledgement does not matter
> - "[]" where it does not.
For '[]', I guess you meant "where it does."
> You would find the old grammar with:
> 1[AAA,BBB,CCC]
>
Thanks,
Amit
