On 2020-04-11 00:44, Andres Freund wrote:
> I think there's also some advantages of having it in a single statement
> for poolers. If a pooler analyzes BEGIN AFTER 'xx/xx' it could
> e.g. redirect the transaction to a node that's caught up far enough,
> instead of blocking. But that can't work even close to as easily if
> it's
> something that has to be executed before transaction begin.
>
I think that's a good point.
Also, I'm not sure how we'd expect a wait-for-LSN procedure to work
inside a single-snapshot transaction. Would it throw an error inside a
RR transaction block? Would it give a warning?
--
Anna Akenteva
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The Russian Postgres Company