问题在于统计数据并不是对现实的客观衡量；它们只是一个最佳估测值。
The problem is that the statistics aren't an objective measure of reality; they are simply a best approximation.
这个值包含调整内存堆大小花费的时间和收集调优决策所需的统计数据花费的时间。
This value includes the time spent resizing the memory heaps and the time spent collecting statistics to make the tuning decision.
如果查询谓词中引用的列存在显著的数据值倾斜，那么要确保DB 2了解这一情况，最好是使用RUNSTATS生成列值柱状图统计数据。
If a significant data value skew exists for a column referenced in a query predicate, make sure that DB2 knows this, preferably by generating column-value histogram statistics using RUNSTATS.
聚合实例时捕捉数字值的统计数据的出色方法。
Aggregate instances are a great way to capture statistics on numerical values.
统计数据丢失：当统计数据丢失后，优化器假设一个默认值来确定成本，这非常不准。
Missing statistics: When statistics are missing, the optimizer assumes the default values to determine costs, which could be completely inaccurate.
这一统计数据不代表用户数的绝对指示，但却相对于SERVER_SESSION _ TIMEOUT值。
This statistic does not represent an absolute indication of the number of users, but a relative one to the SERVER_SESSION_TIMEOUT value.
连续运行的updatestatistics将使用这些值来判断现有的统计数据是否过时。
These values are then used by consecutive update statistics runs to determine if existing statistics are good or stale.
优化器的行为受三个关键因素的影响：Informix配置文件中OPTCOMPIND参数的值、查询命令和内部统计数据的准确性。
The behavior of the optimizer is influenced by three key factors: the value of OPTCOMPIND parameter in the Informix configuration file, query directives, and the accuracy of internal statistics.
根据济阳坳陷137个砂体充满度的统计数据，计算了特征值，作出了因子载荷分布图。
Based on the statistical data for the sufficient degree of 137 sand bodies in Jiyang sag to calculate the characteristic value, and make the distribution map of factor loading.
点内插主要用于自然地理数据的插值，而面内插则主要用于社会经济统计数据的插值问题。
The point interpolation is mainly used to deal with natural geography data and the areal interpolation is usually used to solve the interpolation problem of social economic statistic data.
德国官方统计数据显示，七月份出口额下降1.8%，远超预想值。
German exports fell by 1.8% in July, much more than expected, official figures have shown.
来自银行的统计数据显示：在本年度的前5个月份中，北京、上海和深圳的平均房价同比下滑幅度创下了最高值1.6%。
By the bank's calculations, property prices in Beijing, Shanghai and Shenzhen recorded an average decline of 1.6% year-over-year in the first five months of this year.
来自银行的统计数据显示：在本年度的前5个月份中，北京、上海和深圳的平均房价同比下滑幅度创下了最高值1.6%。
By the bank's calculations, property prices in Beijing, Shanghai and Shenzhen recorded an average decline of 1.6% year-over-year in the first five months of this year.
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