The third command samples 15% of all rows, does not collect distribution statistics, and also applies sampling to indexes which the first and second commands didn't.

第三个命令抽取 15% 的行，但是不收集分布统计信息，并对索引也应用了抽样，这不同于第一个命令和第二个命令。

youdao

SQS USES message sampling based on weighted random distribution, and it returns messages only from the sampled subset of servers when you query for messages.

SQS使用基于加权随机分布的消息取样，在查询消息时，它只从取样的一部分服务器返回消息。

youdao

To find the sampling distribution of the Chi Square statistic, simply take the outcome of each experiment and compute a Chi Square statistic for that result.

为了找到X平方分布统计的抽样分布，只需获取每次实验的结果，并且计算该结果的x平方分布统计。

youdao

This sampling helped to work out the distribution and mix of light wavelengths and their relative intensities found in a scene, said Mr Hunt.

BBC: Lens-less camera emerges from metamaterials work

It also carries the risk of producing an inaccurate picture of the overall distribution of moisture, as the spots chosen for sampling may be considerably damper or drier than the soil just a few metres away.

ECONOMIST: Winemaking and radar