Simon Riggs wrote:
- yes, the random sampling is random - please read the code and comments
- yes, I would expect the results you get. If you sample 5% of rows and
each block has on average at least 20 rows, then we should expect the
majority of blocks to be hit.
and it seems from the benchmark posted to this list that random is
_very_ expensive (probably because the random reads are spread out so
well, that we do alot of I/O instead of just logical I/O from some cache)
regards,
Lukas
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