英语释义

1. a number by which the normal exposure time must be multiplied to compensate for the use of a color filter with a given photographic material and source of illumination

片语

Uv Filter Factor紫外线过滤因子

filter efficiency factor f过滤效率因子f

filter correction factor滤波校正因子

filter q factor滤波器q值

lightdiffusive filter factor滤光因数

filter clogging factor滤波因数

filter cake stuck factor泥饼粘滞系数

inverse filter factor反滤波因子

light filter factor滤光器因数

英汉例句

• since no frequency statistics were collected (max_freq=(missing)), the filter factor of each predicate is calculated based on the assumption that the data is uniformly distributed on the columns.

  由于未收集到频度信息（max_freq=(missing)），每个谓词的过滤因子是在假设数据均匀分布在各列的基础上计算的。

• for sql statements with variables, the optimizer uses a default filter factor to determine the best access path at bind time.

  对于带变量的sql语句，优化器会使用一个默认过滤因子在绑定时确定最佳访问路径。

• ff (see number 6 in figure 5): filter factor for the predicate.

  ff（见图5中6）：谓词的过滤因子。

• according to the annotation information in the figure, the table reference cust_customer (ccus) has two local predicates which are very selective, with filter factor 0.00727 and 0.004, respectively.

  根据图中的注释信息，优先表 cust_customer (ccus)有两个本地谓词，其选择性很强，各自的过滤因子分别是0.00727和0.004。

• hence, the filter factor of 19/32 = 0.59375 matches the filter factor estimate in the access plan for this predicate

  因此筛选因子是 19/32 =0.59375，和访问计划中估计的该断言的筛选因子匹配。

• the noise will be effectively oppressed if filter factor is added to the data involved noise.

  对于含有噪声的数据，加入滤波因子可以在一定程度上抑制噪声。

• the filter factor indicates how selective the predicate is.

  过滤因子表示谓词的选择性有多强。

• if you want to further see if the filter factor estimates at tbscan(3) make sense, you should generate a count for each predicate individually. for example

  如果希望进一步看看tbscan(3)估计的筛选因子是否合理，应该分别对每个断言生成计数。

• for example, the column cardinality of cust_city is 1376, thus the filter factor of the predicate ccus.cust_city=「singapore」 is computed as 1/1376=0.00727.

  例如，cust_city的列基数是1376，因此谓词ccus.cust_city =「singapore」的过滤因子计算为 1/1376=0.00727。

• since it is a range predicate and there are no frequency and histogram statistics available, the filter factor is calculated with the basic statistics information high2key and low2key.

  由于它是范围谓词，而且没有频度和直方图统计数据可用，过滤因子是用基础统计信息high2key和low2key计算得出的。

• the estimate for qualified_rows is obtained by multiplying the table cardinality (560,273 records) by the predicate filter factor (0.0014%).

  用表基数（560,273 条记录）与谓词过滤因子 (0.0014%) 相乘就获得了 qualified_rows 的估计值。

• the query annotation for this predicate shows that the predicate filter factor (ff) is 0.000014, or 0.0014%.

  此谓词的查询注释显示谓词过滤因子 (ff)是0.000014，或 0.0014%。

• this is because the optimizer now knows that the predicate state 100 has a high filter factor and therefore only returns the nearly 1,000 cars currently going through the manufacturing process.

  这是因为优化器现在知道，谓词state 100有一个较高的过滤因子，因而只会返回大约 1,000辆正处在生产流程中尚未完工的汽车。

• the filter factor is a number between 0 and 1 that estimates the proportion of rows in a table for which the predicate is true.

  过滤因子是0到1之间的一个数值，它用来评估表中谓词为真的行所占的比例。