On 12 August 2016 at 15:24, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Simon Riggs <simon@2ndquadrant.com> writes:
>> On 11 August 2016 at 17:21, <paddor@gmail.com> wrote:
>>> > If REPEATABLE is not given then a new random sample is selected for each
>>> query.
>>>
>>> the word "sample" should be "seed". Of course it results in a new random
>>> sample as well, but IMHO this sentence is about what happens to the seed in
>>> case REPEATABLE (seed) is omitted.
>
>> Corrected, thanks.
>
> I do not think this is an improvement. The sentence was specifically about
> whether the sample (that is, the set of rows selected) would change. This
> rewording essentially removes that user-visible behavior guarantee, and
> for what? It's certainly not any clearer.
It was supposed to be a correction, rather than an improvement. I saw
the use of the word "sample" as an error.
But now you mention it, I agree with you. Let's put it back to say
"sample" but also explain where that new sample comes from... my
attempt to explain this better is in square brackets
"If REPEATABLE is not given then a new random sample will be taken for
each query [based upon the global seed value for the current user.]"
--
Simon Riggs http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
