Re: pgsql: Implement waiting for given lsn at transaction start

Alexander Korotkov <akorotkov@postgresql.org> writes:
> Implement waiting for given lsn at transaction start
> This commit adds following optional clause to BEGIN and START TRANSACTION
> commands.
>   WAIT FOR LSN lsn [ TIMEOUT timeout ]

This seems like a really carelessly chosen syntax --- *three* new
keywords, when you probably didn't need any.  Are you not aware that
there is distributed overhead in the grammar for every keyword?
Plus, each new keyword carries the risk of breaking existing
applications, since it no longer works as an alias-not-preceded-by-AS.

I have no particular opinion on the value of the feature, but I wish
a different syntax had been chosen.

            regards, tom lane