Jeff Davis wrote:
> And the next question is what commands to add to change state. Ideas:
>
> CHECKSUMS ENABLE; -- set state to "Enabling"
> CHECKSUMS DISABLE; -- set state to "Off"
>
> And then to get to the "On" state, you have to run a system-wide VACUUM
> while in the "Enabling" state. Or, if the above syntax causes problems,
> we can make all of these into VACUUM options.
There's no such thing as a system-wide VACUUM. The most you can get is
a database-wide VACUUM, which means you'd have to store the state
per-database somewhere (presumably the pg_database catalog), and perhaps
pg_control could have it as a system-wide value that's computed as the
minimum of all database states (so it stays "enabling" until all
databases have upgraded to "on").
--
Álvaro Herrera http://www.2ndQuadrant.com/
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