Ryan Murphy wrote:
> My question kind of remains though - does that mean that having any nulls
> in the tuple loses the ability to use the tupleDesc cache? and how much of
> a performance impact is this? I'm sure there's a good reason why you can't
> really use the cache if you have a null column, just was curious of the
> implications.
attcacheoff can only be set positive for fields preceding any varlena
(typlen<0, but including the first such) or nullable values. I don't
know how much faster it is with the cache; you can measure it if your
curiosity is strong enough -- just set the first column to nullable.
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Álvaro Herrera https://www.2ndQuadrant.com/
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