For MDC, a key decision is which columns ( s) will serve as MDC dimensions. 对于MDC,一个关键的决定是用哪些列作为MDC维。
For example, an MQT can be partitioned using MDC or TP. 例如,可以使用MDC或TP对MQT分区。
For example, when MDC was introduced, its index aspects did not change DPF aspects of indexes. 例如,当引入MDC时,它的索引方面不会改变DPF在索引方面的工作方式。
Efficiency of SAP BW with key BI-related objects like MDC tables for even faster performance. SAPBW的高效性通过关键的BI有关对象,如MDC表,以获得更快的性能。
In addition to range-partitioning, multi-dimensional clustering ( MDC) can be used to cluster the rows in a table based on one or more columns. 除了范围分区,多维集群(MDC)也可用来根据一个或多个列对表内的行进行集群。
TP, introduced in DB29, is similar to MDC in that it enables rows with similar values to be stored together. TP是在DB29中引入的,与MDC类似,它也可以将具有近似值的行存储在一起。
MDC contributes by making it efficient to retrieve data. MDC对性能的贡献在于提高检索数据的效率。
The Design Advisor now provides advice on materialized query tables ( MQTs), multidimensional clustering tables ( MDCs), and Data Partitioning Feature ( DPF) partitioning keys, in addition to indexes. 除了索引外,DesignAdvisor还提供关于物化查询表(MQT)、多维集群表(MDC)和数据分区功能(DataPartitioningFeature,DPF)分区键的建议。
A typical design is an MDC dimension for a column representing date plus dimensions on0 to3 other columns such as region and product_type. 典型的设计是用一个表示日期的列作为一个MDC维,再加上0到3个其他列作为其他维,例如region和producttype。
As well, the MDC feature includes block indexes that contain an entry for each block of data rather than for individual rows. 而且,MDC特性还包括块索引,在块索引中,对于每个块的数据(而不是每一行的数据)都有一个条目。
Determining the distribution key for DPF is not affected by whether or not MDC and TP are also being used. 是否使用MDC和TP对于决定DPF的分布键没有影响。
This new DELETE algorithm in DB2 V8.2.2 can drastically reduce the logging and processing associated with the deletion of rows in an MDC table and its corresponding block indexes. DB2V8.2.2中这种新的DELETE算法可以显著减少与MDC表中行及其相应的块索引的删除相关的日志记录和处理。
Faster inserts: MDC tables reduce page contention and locking which make it conducive to perform inserts using multiple, parallel streams. 更快的插入:MDC表减少了页面争用和锁,因此有助于使用多个并行的流来执行插入。
This article introduced the following DB2 table design features: table partitioning, MDC, DPF, and MQT. 本文介绍了以下DB2表设计特性:表分区、MDC、DPF和MQT。
Multidimensional-You can roll out data on any dimension in an MDC table. 多维-现在可以转出MDC表中任何维上的数据。
Essentially, MDC is a feature that maximizes performance of queries, especially those commonly found in data warehouses. 实际上,MDC是一个能最大化查询性能的特性,对于数据仓库中常用的查询更是如此。
MDC will only benefit those queries that include dimension columns. MDC只对那些包括维列的查询有好处。
For example, an MQT can be created on one or more tables that uses MDC and TP. 例如,可以在一个或多个使用MDC和TP的表上创建MQT。
When DB2 encounters an INSERT on an MDC table, it looks for a free block. 当DB2碰到对MDC表的INSERT操作时,它寻找一个空闲的块。
TP cannot be used to rectify a poor MDC design. TP不能用于纠正不好的MDC设计。
( Note: If you also want MDC recommendations, a representative sample of data is required in the tables, as well). (注意:如果您还想要MDC建议,那么在表中还需要代表性的样本数据)。
On the other hand, with MDC it is advisable to pre-sort the data according to the MDC dimensions. 另一方面,如果使用MDC,建议预先根据MDC维对数据进行排序。
When scanning an MDC table, block locking could be deferred for an index scan. 当扫描一个MDC表时,对于索引扫描,块锁可以推迟。
The MDC granularity can be finer-grain than the TP data partition size. MDC的粒度可以比TP数据库分区更细一些。
This paper describes the relationship between DCT high frequency coefficients of images and sampling schemes of multiple description coding ( MDC). 分析了图像DCT高频系数与不同采样方式的多描述图像编码的关系,得出了二者之间存在相关性的结论。
This circuit is used in BES Trigger System to reject the background caused by interference in MDC. 该电路用在北京谱仪触发判选系统中,作为排除由于干扰信号造成主漂移室成片着火的本底事例。
It combines the advantages of scalable coding and multiple description coding ( MDC), and can provide relatively high transmission reliability and rate adaptation. 该编码器结合了多描述编码(MDC)和分层编码的优点,能够提供稳定的传输质量和速率的自适应。
To investigate CAR's task in a healthy organism, the MDC-scientists switched off the CAR-gene in adult mice. 为了调查CAR在一个健康机体中的作用,MDC的科学家敲除成年小鼠的CAR基因。
The Presto Developer Edition is available for download to members of the MDC community. Presto开发版面向MDC社区会员提供下载。