Re: A question about ExplainOnePlan()

On 12/13/06, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
> "Gurjeet Singh" <singh(dot)gurjeet(at)gmail(dot)com> writes:
> > Can we avoid calls to Executor{Start|End}() here, or is it necessary
> to
> > call them even for non-ANALYZE case?
>
> No; at least not unless you want to duplicate the permission-checking
> machinery inside ExecutorStart.

I had seen the ExecCheckRTPerms() call inside InitPlan(), but didn't know
that we considered even the EXPLAIN output to be so sensitive.

Otherwise EXPLAIN could be used to
> obtain information about tables you're not supposed to be able to read
> (for instance, the estimated number of rows matching a WHERE condition
> could be sensitive information).
>
> Also, you'd have to uglify explain.c quite a lot to be able to handle
> the case of traversing a plan tree without a matching planstate tree.

Thanks.

--
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