Re: is ErrorResponse possible on Sync?

Thanks!

I work on CockroachDB - which is wire-compatible with Postgres - so I'm
interested in what the server can and cannot do.


> Uh ... I don't think Sync itself can fail.  Any ErrorResponse you see
> there is really from failure of some prior command.


Hmm, this got me curious. If Sync itself cannot fail, then what is this
sentence really saying: "This parameterless message (ed. Sync) causes the
backend to close the current transaction if it's not inside a BEGIN/COMMIT
transaction block (“close” meaning to commit if no error, or roll back if
error)." ?
This seems to say that, outside of BEGIN/END, the transaction is committed
at Sync time (i.e. if the Sync is never sent, nothing is committed).
Presumably, committing a transaction can fail even if no
previous command/statement failed, right?



>   The Sync is really
> delimiting how much stuff you'd like to skip in case of a failure.
> Basically this is to allow pipelining of commands, with the ability to
> discard later commands if an earlier one fails.
>
> But in any case, no, Sync would not suppress an error message if
> one is needed.
>
>                         regards, tom lane
>