Re: Unused variable scanned_tuples in LVRelStats

On Tue, Jul 4, 2017 at 10:13 PM, Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com> wrote:
> scanned_tuples variable in LVRelStats is introduced by commit b4b6923e
> but it seems to me that it's actually not used. We store num_tuples
> into vacrelstats->scanned_tuples after scanned all blocks, and the
> comment mentioned that saving it in order to use later but we actually
> use num_tuples instead of vacrelstats->scanned_tuples from there. I
> think the since the name of scanned_tuples implies more clearer
> purpose than num_tuples it's better to use it instead of num_tuples,
> or we can remove scanned_tuples from LVRelStats.

I think we should only store stuff in LVRelStats if it needs to be
passed to some other function. Data that's only used in
lazy_scan_heap() can just be kept in local variables. We could rename
the local variable, though, since I agree with you that scanned_tuples
is clearer.

--
Robert Haas
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