| 释义 |
car·di·nal·i·ty AHDˌkärdᵊnˈaləd.ē COCA¹⁷²⁸¹⁶BNC⁹⁷²³³⁺⁷iWeb³¹²⁷¹
基本英英记法例句例句
n.基数¹⁰⁰
Noun:
mathematics the number of elements in a set or group considered as a property of that groupingcardinal-ity名词⇒n.基数
名词100%
用作名词The singular and plural names are used depending on thecardinalityof the relationship.使用单数或复数名称取决于关系的基数。
We describe a parent class whose elements have a property withcardinalityequal to one.我们描述一个父类，它的元素有一个基数等于一的属性。 Give lower priority to operators that do not change the cardinality of the plan.
为不改变计划基数的操作分配较低的优先级。 ibm
It is common practice to assume the predicates are independent of each other when computing their combined filtering effect on the cardinality estimate.
在计算谓词对于基数估计值的组合过滤效果时，通常会假设这些谓词彼此之间是独立的。 ibm
The intermediate profile is more technically oriented with details on data models, expressions, and cardinality information and is more suited for business architects.
中级配置文件在技术上更针对于数据模型的细节、表达式及基数信息，并且它更适合于业务架构师。 ibm
The optimizer is dependent on accurate cardinality estimates to properly compute the cost of each query access plan considered.
优化器凭借精确的基数估计值来准确计算出每一个待定查询访问计划的成本。 ibm
The cardinality estimate is slightly higher than the actual value of4 since the column group statistic is a uniform distribution statistic.
由于列组统计信息是一个均匀分布的统计信息，所以基数估计值比实际值4稍高了一些。 ibm
They define a template for instances of business objects and enable you to specify properties and relationships, as well as define custom cardinality.
业务模型为业务对象的实例定义一个模板，并让您能够指定属性和关系以及定义定制基数。 ibm
To the right of each table reference is the table cardinalityin terms of both number of records and number of pages and the estimated number of qualified rows.
每个表引用的右边是表基数依据记录的数量和页面的数量以及合格行的估计数量。 ibm
Under-estimating the cardinality could lead the optimizer to choose a sub- optimal access plan.
而基数值的低估又会导致优化器选择一个次优的访问计划。 ibm
With three predicates applied in the WHERE clause, assuming they are independent results in the optimizer underestimating the cardinality.
在 WHERE子句中应用了三个谓词，如果假设它们是独立的话，会导致优化器低估基数。 ibm
And, as expected, when the number of elements specified in an array constructor exceeds the array's maximum cardinality, DB2 notifies you of an error.
而且，正如所期望的那样，阵列构造函数中指定的元素数量超过阵列的最大基数时， DB2会提示您一个错误。 ibm
At each operator in the access plan, the optimizer estimates the cardinality output from the operator.
对于访问计划的每个操作符，优化器将估计该操作符的基数输出。 ibm
Both statistical views and REOPT allow the optimizer to compute a more accurate cardinality estimate and consequently choose an optimal query execution plan.
统计视图和 REOPT都使优化器可以计算出更精确的基数估计，而后选择一个最佳查询执行计划。 ibm
For example, cardinality restrictions specify the number of relationships that a class of individuals can participate in.
例如，基数限制指定某类个体可以参与的关系的数量。 ibm
Generate the access plan and see what the optimizer estimates the total cardinality Number of rows returned by the query will be.
生成访问计划，查看优化器对该查询返回的总基数行数的估计值。 ibm
Specify attribute types and cardinality: Specify several properties of one attribute, and then repeat that step for all attributes.
指定属性类型和基数：指定一个属性的几个特征，然后为所有属性重复该步骤。 ibm
Statements involving larger tables and joins of two or more tables are more likely to exhibit a change in query access plan as a result of the improved cardinality estimate.
如果语句涉及到更大的表格和两个或者更多个表的连接的话，查询访问计划就很可能会因为基数估计值的提高而改变。 ibm
Strive for no more than one call after a single cardinality find on a home, or a next on an iterator retrieved from a collection.
在本机上找到一个基数，或者通过迭代器从集合中检索到下一个基数后，尽量使用不超过一个调用。 ibm
The application of one or more predicates may reduce the output stream cardinality.
应用一个或更多谓词可以减少输出流基数。 ibm
The higher the cardinality, the more probes into the inner table, one per qualifying outer record.
基数越高，进入内部表、每一条合格的外部记录的探测就越多。 ibm
The examples described in this article are simple in order to illustrate how to improve the cardinality estimate.
为了更好的说明如何提高基数估计值，本文中所描述的例子都很简单。 ibm
The number shown in each node is the optimizer's estimate for the cardinality of the underlying data source or operation node.
每一个节点上显示的数字都是优化器对基础数据源或操作节点的基数的估计。 ibm
Therefore, omitting the maximum cardinality does not have any impact on the amount of allocated memory.
因此，省略最大基数不会对已分配的内存量产生任何影响。 ibm
This example illustrates the effect that partial statistics have on the ability of the optimizer to estimate the cardinality.
这个示例解释说明了部分统计信息对于优化器估计基数的能力的影响。 ibm
Using the same sample data just discussed above, the following illustrates the difference in cardinality estimates with and without the use of statistical view for the query.
下面使用以上讨论的相同的示例数据，阐释在使用和不使用查询的统计视图的情况下基数估计的差别。 ibm
With this method, we can collect real cardinality for access plan operators.
通过这种方法，我们就能够为访问操作者收集实际基数。 ibm
You may have noticed that the query access plan itself did not change with the increase in cardinality estimate.
您可能已经注意到了，查询访问计划本身并未随着基数估计值的增大而改变。 ibm
Cardinality affects join orders and join methods to a large extent.
这个基数会大大影响连接顺序和连接方法。 ibm
Cardinality estimation is a process by which the optimizer uses statistics to determine the size of partial query results after predicates are applied or aggregation is performed.
基数估计是这样一种过程：在应用了谓词或执行了聚集之后，优化器使用统计信息确定部分查询结果的大小。 ibm |