If your intention is a real "between" predicate, then the execution plan on the right is much better, because a single range scan with a start-top predicate delivers the matching row IDs only.
如果您的目的是要实现真正的“between”谓词,则右侧的执行计划会更好一些,因为带有启动谓词的单个范围扫描仅传递匹配的行id。
Index scan (IXSCAN) with matching predicates.
使用匹配谓词的索引扫描(IXSCAN)。
Typically, a non-matching index scan is chosen by the optimizer when the underlying index provides benefits such as index-only access, avoids sort, or some similar benefit.
通常情况下,在基础索引提供好处(如唯一索引访问、避免排序或一些类似的好处)时,可通过优化器选择非匹配索引扫描。
An index scan can be non-matching, which means that there are no restrictions in the scan of the underlying index.
索引扫描可以是非匹配的,这意味着在基础索引的扫描上没有限制。
If you ask Google a question, the search engine's computers scan the Web for matching search terms and come up with answers that make the most sense statistically.
如果你在Google中提一个问题,搜索引擎会扫描Web页面和匹配搜索字段,然后得出从统计角度出发认为最有意义的答案。
KMP scan algorithm is improved by means of the analysis of string pattern matching BF and KMP. The complexity analysis reveals that the improved algorithm, KMPA, is more effective than KMP.
通过对字符串模式匹配BF和KMP算法的分析,提出了改进KMP扫描算法的方法,并通过对算法的复杂性进行分析,结果表明:改进后的算法KMPA比算法KMP更有效。
We segmented input text. utilizing the methods of Maximum Matching and Reverse Maximum Matching, and found ambiguous word through two-way-scan method.
本文在利用正向最大匹配方法和逆向最大匹配方法来对输入文本进行预切分,并通过双向扫描的方法检测歧义字段。
Normal Distributions Transform (NDT) is used in scan-matching based SLAM, and map-building is implemented in larger scale indoor environment by home service robots.
将正态分布变换(NDT)应用于基于扫描匹配的SLAM中,实现了家庭服务机器人较大规模室内环境下的建图。
Normal Distributions Transform (NDT) is used in scan-matching based SLAM, and map-building is implemented in larger scale indoor environment by home service robots.
将正态分布变换(NDT)应用于基于扫描匹配的SLAM中,实现了家庭服务机器人较大规模室内环境下的建图。
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