Re: Advice request : simultaneous function/data updates on many databases

On 2020-03-04 14:42:01 -0800, Guyren Howe wrote:
> On Mar 4, 2020, at 14:33 , Rory Campbell-Lange <rory(at)campbell-lange(dot)net> wrote:
> Essentially we wish to reduce the window where the frontend and backend
> aren't synchronised.
>
> If we have (for example) 200 databases which each take 2 seconds to
> update, a client could be on the wrong frontend code for over 6 minutes.
>
>
> Send each of the servers a PL/PGSQL method that executes all the things in a
> transaction and then waits until the same clock time to commit.

Last time I looked, some DDL commands (especially "drop table") took an
exclusive lock on the affected table. So you may want to keep
transactions which execute such commands very short to prevent them from
blocking other transactions for a noticeable amount of time.

hp

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