From the performance perspective, this is considered a very efficient join operation, because the cost for scanning the inner table is optimal via unique access through a unique index.
从性能的角度来看,这被认为是一个非常有效的联接操作,因为通过贯穿唯一索引的唯一访问扫描内部表的成本是最优的。
Creating an index page, of all articles in a directory or in total, requires scanning the file system for available files.
创建一个索引页,将所有文章都放在一个目录或所有目录中,这样如果想要得到可用的文件就必须扫描该文件系统。
Thus, the search in a large file using a hash index is faster than scanning the entire file.
因此,对于较大的文件,使用hash索引进行搜索比扫描整个文件更快。
Each of these operations: redistribute, table reorg, index create, and runstats require scanning the table data once.
这些操作中:redistribute、table reorg、indexcreate和runstats,每个操作都需要扫描一次表数据。
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。
Another goal was to also enable usage of pre-indexed information, so that there would actually be no need for the scanning itself; e.g. one could pre-index all of jar's annotations during the build.
另一个目标是启用预先索引信息,这样就无需扫描了。比如说,我们可以在构建过程中预先索引所有jar的注解信息。
Annotate: So called optimizing is WHERE clause used index, cannot optimize happened to express scanning or additional expense namely.
注释:所谓的优化就是WHERE子句利用了索引,不可优化即发生了表扫描或额外开销。
We research the various index modulation methods and design the scanning device to realize the apodized exposure.
研究了光纤光栅不同折射率调制的实现方法,并设计研制了实现变迹曝光法的扫描装置。
Methods Liver scanning was performed with a high frequency transducer to measure the velocity acceleration time and resistant index of portal vein and hepatic artery after finishing the anastomosis.
方法选用高频手术专用探头,于手术中门静脉、肝动脉吻合完成后立即测量肝动脉及门静脉血流速度,并计算快速充盈时间及阻力指数。
This way the database engine will stop scanning for records after it finds just 1, instead of going thru the whole table or index.
数据库引擎在找到一条记录后就停止继续扫描,而不是扫完整张表或者索引。
It's influence on the properties of anhydride cured epoxy resin was studied by scanning electron microscope, heat analysis, limiting oxygen index determination and other methods.
并用扫描电镜、热分析、氧指数和机械性能测定等方法研究了HB—1对酸酐固化的环氧树脂性能的影响。
The instrument recognition system made by video scanning has realized the reading recognition of index-instrument and digital display instrument.
设计的视频扫描表头识别系统,实现了指针式仪表和数字显示仪表的识别。
The instrument recognition system made by video scanning has realized the reading recognition of index-instrument and digital display instrument.
设计的视频扫描表头识别系统,实现了指针式仪表和数字显示仪表的识别。
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