Re: Bugs in CREATE/DROP INDEX CONCURRENTLY

"Kevin Grittner" <kgrittn@mail.com> writes:
> To put that another way, it should be done at a time when it is sure
> that no query sees indisvalid = true and no query has yet seen
> indisready = false.  Patch attached.  Will apply if nobody sees a
> problem with it.

The above statement of the requirement doesn't seem to match what you
put in the comment:

> +      * All predicate locks on the index are about to be made invalid. Promote
> +      * them to relation locks on the heap. For correctness this must be done
> +      * after the index was last seen with indisready = true and before it is
> +      * seen with indisvalid = false.

and the comment is rather vaguely worded too (last seen by what?).
Please wordsmith that a bit more.
        regards, tom lane