Re: Predicate locking

Kevin Grittner wrote:
>> I don't think Vlad is being unreasonable here; he's provided a
>> test case demonstrating the behavior he'd like to see, and shown
>> it doesn't work as expected.
>>
>
> ... on a toy table with contrived values. How different is this
> from the often-asked question about why a query against a four-line
> table is not using the index they expect, and how can we expect it
> to scale if it doesn't?

It's not, but in that case I've been known to show someone that the
behavior they're seeing doesn't happen on a larger table. My point was
just that no one has really done that here yet: provided an example
showing SSI serialization working as a substitute for predicate locking
in this sort of use case. I trust that the theory is sound here, and
yet I'd still like to see that demonstrated. This is why I launched
into making a less trivial test case.

--
Greg Smith 2ndQuadrant US greg(at)2ndQuadrant(dot)com Baltimore, MD
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