distinct cardinality的意思|示意

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不同的基数


distinct cardinality的网络常见释义

于相异基数 位图索引位图索引对于相异基数(distinct cardinality)低的数据最为合适。位图索引在读密集的环境中能很好地工作,但是对于写密集的环境则极不适用。

distinct cardinality相关例句

COLCARDF (see number 4 in Figure 5) : column cardinality, which denotes the estimated number of distinct values in the column.

COLCARDF(见图5中4):列基数,表示评估的列中不同值的数目。

To achieve this goal, the partitioning key should be selected on the columns that have high cardinality, or in other words, that contain a large number of distinct values.

为了实现此目标,分区键应该在具有较高基数(换言之,即包含大量不同值)的列上选择。

The indexed columns have low cardinality, that is, the number of distinct values is small compared to the number of table rows.

索引列有较低的相似度,这就意味着,在表的记录中相同值的数据的数量比较少。