Amit Kapila wrote:
> I think it is because heap_getattr() is not that cheap. We have
> noticed the similar problem during development of scan key push down
> work [1].
One possibility to reduce the cost of that is to use whole tuple deform
instead of repeated individual heap_getattr() calls. Since we don't
actually need *all* attrs, we can create a version of heap_deform_tuple
that takes an attribute number as argument and decodes up to that point.
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Álvaro Herrera https://www.2ndQuadrant.com/
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