On 2018-Dec-11, Jose Luis Tallon wrote:
> * EXPLAIN PERFORM ALTER TABLE (EXPLAIN EXEC?) would explain + do
>
> ...and bonus points for explaining each step just before it is
> performed. This way, It'd be easy for users to verify that a particular step
> (i.e. table rewrite) is the one taking æons to run or hammering the storage.
We have a mechanism for reporting progress of DDL commands. Currently
as far as I remember it's able to report VACUUM progress; there's a
patch in commitfest to add support for CLUSTER. Rahila Syed in
https://www.pgcon.org/2017/schedule/attachments/472_Progress%20Measurement%20PostgreSQL.pdf
proposed ways to have it report for ALTER TABLE also, though I don't
think anyone has worked on that.
I think these two things are separate.
--
Álvaro Herrera https://www.2ndQuadrant.com/
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