Re: Incorrect visibility test function assigned to snapshot

On Wed, May 30, 2018 at 09:28:54AM -0400, Alvaro Herrera wrote:
> 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?

Uh, are we going to fix this anyway? Seems we should.

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Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

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