The rest of this section takes you through the access path graph one more time from the data flow perspective so that you can gain a full understanding of the performance aspect of query execution.
本节的其余部分再一次以数据流的观点向您介绍访问路径图以便您可以在查询执行的性能方面获得充分的理解。
XML-based query languages are constructed to reach any arbitrary position within an XML document's "graph" using sequences of edge labels and delimiters representing a path.
基于XML的查询语言被构造来，使用表示路径的边标签和定界符序列达到XML文档图中的任意位置。
An access path graph not only describes the "operational details" of query execution, it also describes how the data flows.
访问路径图不但描述“操作细节”，而且描述数据如何流动。
The description of each operation includes a Query Tuner access path graph that explains its operational semantics.
每一个操作的描述都包括一个解释其操作语义的QueryTuner访问路径图。
Table 1 describes the input, output, and function of several operation nodes that typically appear in an Optim Query Tuner access path graph.
表1描述通常出现在OptimQueryTuner访问路径图上的输入、输出和几个操作节点的功能。
An index scan is typically shown in Query Tuner as a group of four nodes in the access path graph.
在访问路径图中，一个索引扫描通常作为一组四个节点显示在QueryTuner上。
The SQL statement in Listing 2 creates the access path graph shown on the right side of the Optim Query Tuner screenshot in Figure 2.
清单2中的sql语句创建如图2上的OptimQueryTuner截图右侧所示的访问路径图。
Figure 6 is the access path graph generated by query Tuner for the sample query in this article.
图6是QueryTuner为本文中大的查询样例生成的访问路径图。
This section illustrates how the query Tuner query annotation and access path graph can help you analyze access paths and SQL performance.
本部分说明QueryTuner查询注释和访问路径图如何帮助您分析访问路径和SQL性能。
Figure 1 is the access path graph generated by Optim query Tuner for the query shown in Listing 1.
图1是通过清单1所示的适用于查询的OptimQueryTuner生成的访问路径图。
At first, an algorithm is proposed, which rewrites a regular path expression based XML query as a group of simple path expression based queries using mapping information (mapping graph).
首先提出了一个利用映射信息(映射图)将带正则路径表达式的XML查询重写为一组简单路径查询的算法。
At first, an algorithm is proposed, which rewrites a regular path expression based XML query as a group of simple path expression based queries using mapping information (mapping graph).
首先提出了一个利用映射信息(映射图)将带正则路径表达式的XML查询重写为一组简单路径查询的算法。
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