RUNSTATS with column group statistics.
包含列组统计信息的runstats。
Column group Statistics obtains the number of distinct combinations of values for a group of columns.
列组(Column Group)统计信息将获得一组列的不同值组合的数目。
This example illustrates the effect of column group statistics on a qualifying OR predicate. Consider the following query on the EMPLOYEE table.
这个例子解释说明了列组统计信息对一个合格的OR谓词的影响。
Collecting statistics of individual columns may not be enough to provide the information required, so you need to collect column group statistics.
收集单个列的统计数据还不足以提供所需信息，因此您需要收集列组统计数据。
Sometimes, column group, or like statistics options can be useful.
有时候，列组或类似的统计选项会很有用。
The following example illustrates using RUNSTATS to collect catalog statistics that capture column group information
下列例子说明了如何使用RUNSTATS收集捕获了列组信息的目录统计信息
The precision for the frequency and quantile statistics can be modified for an individual column or a group of columns.
可以为单个列或一组列修改频率和分位数统计信息的精确度。
The precision for the frequency and quantile statistics can be modified for an individual column or a group of columns.
可以为单个列或一组列修改频率和分位数统计信息的精确度。
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