Re: REVIEW: EXPLAIN and nfiltered

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> On Thu, Jan 20, 2011 at 3:47 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> BTW, is it just me, or is the terminology "number filtered" pretty
>> confusing/ambiguous in itself? It doesn't seem at all clear to me
>> whether that's the number of rows passed by the filter condition or
>> the number of rows rejected. Perhaps "nremoved" would be clearer.

> I think filtered is pretty clear and like it... removed sounds like
> you deleted something.

Well, you did delete something, no? There are rows that aren't in the
output that would have been there if not for the filter condition.

And, btw, one person thinking it's clear doesn't make it so. There
are actually three numbers that could be involved here: the number of
rows arriving at the filter, the number passed by it, and the number
rejected by it. I think that "nfiltered" could possibly mean any of
those three. A non-native speaker of English would be even less
likely to be sure of what was meant.

regards, tom lane