On 9/4/17, 8:16 PM, "Michael Paquier" <michael.paquier@gmail.com> wrote:
> So vacuum_multiple_tables_v14.patch is good for a committer in my
> opinion. With this patch, if the same relation is specified multiple
> times, then it gets vacuum'ed that many times. Using the same column
> multi-times results in an error as on HEAD, but that's not a new
> problem with this patch.
Thanks!
> So I would tend to think that the same column specified multiple times
> should cause an error, and that we could let VACUUM run work N times
> on a relation if it is specified this much. This feels more natural,
> at least to me, and it keeps the code simple.
I think that is a reasonable approach. Another option I was thinking
about was to de-duplicate only the individual column lists. This
alternative approach might be a bit more user-friendly, but I am
beginning to agree with you that perhaps we should not try to infer
the intent of the user in these "duplicate" scenarios.
I'll work on converting the existing de-duplication patch into
something more like what you suggested.
Nathan