density估计的列的单值加权平均选择性,不计算存储在行中的单值选择性大的选择性。

density估计的列的单值加权平均选择性,不计算存储在行中的单值选择性大的选择性。的英文翻译

基本释义

• Density An estimate of the weighted average selectivity of a single value for the column, not counting the selectivity of large single value selectivities stored in the row.