Re: Incorrect visibility test function assigned to snapshot

On 2018-May-30, Antonin Houska wrote:

> In the header comment, SnapBuildInitialSnapshot() claims to set
> snapshot->satisfies to the HeapTupleSatisfiesMVCC test function, and indeed it
> converts the "xid" array to match its semantics (i.e. the xid items eventually
> represent running transactions as opposed to the committed ones). However the
> test function remains HeapTupleSatisfiesHistoricMVCC as set by
> SnapBuildBuildSnapshot().

Interesting.  While this sounds like an oversight that should have
horrible consequences, it's seems not to because the current callers
don't seem to care about the ->satisfies function.  Are you able to come
up with some scenario in which it causes an actual problem?

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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