想象一下，当一位游客走近你问路时，你正在当地的城市公园里散步。
Imagine that you are taking a walk in your local city park when a tourist approaches you asking for directions.
不同之处在于硬件，也就是电脑接受司机问路的方式和显示驾驶指令的方式。
The differences come in hardware—the way the computer accepts the driver's request for directions and the way it presents the driving instructions.
最重要的是，问路时要有礼貌。
这里有一些关于如何在国外问路的建议。
Here is some advice on how to ask the way in a foreign country.
我故意拔掉主机与交换机之间的一根 FC电缆，从而中断其中一条访问路径。
I purposely interrupt one of the access paths by pulling off an FC cable between the host and switch.
也不要在街上随便找个陌生人问路。
我走到警察跟前向他问路。
我问路上的人，芜湖有几个医院？
I asked the pedestrians how may hospitals there were in Wuhu.
查询的访问路径：如何访问这些表？
回到美国，迷路时我总是打手机向朋友问路。
Back in the US, whenever I got lost, I would always call a friend for directions on my cell phone.
它知道是该停下问路和选择一致的道路的时候了。
It knows it's time for you to stop, ask directions, and choose the path of alignment.
请记住，优化器使用编目数据决定访问路径。
Keep in mind that this catalog data is what the optimizer USES to make access path decisions.
我曾在附近只是走来走去，或问路的时候碰到了一些好朋友。
I've met some of my good friends by simply walking around in their neighborhood and having to ask for directions.
她说我是个诗人，然后问路者便满脸鄙夷地掉头离开。
She said I was a poet and my questioner turned away contemptuously.
清单8中的sql语句创建如图8所示的访问路径图。
The SQL statement in Listing 8 creates the access path graph shown in Figure 8.
清单5中的sql语句创建如图5所示的访问路径图。
The SQL statement in Listing 5 creates the access path graph shown in Figure 5.
为了查看表描述符，请右键单击访问路径图上的表节点。
To see the table descriptor, right-click the table node in the access path graph.
不一致的统计数据还会误导优化器选择糟糕的访问路径。
The inconsistent statistics may also mislead the optimizer into choosing a bad access path.
本文描述了访问路径的基本概念以及如何解读访问路径图。
This article described the basic concepts of access paths and how to read an access path graph.
假设这是事实，基础访问路径会被认为具有最佳的高可信度。
Assuming this to be the case, the underlying access path is considered optimal with high confidence.
那段时间由于人生路不熟，我们经常在外面要向当地人问路。
At that time, as we were not familiar with the ways, we had to ask the locals for help.
访问路径图不但描述“操作细节”，而且描述数据如何流动。
An access path graph not only describes the "operational details" of query execution, it also describes how the data flows.
然而，对于此示例则选择了一个不同的访问路径，如图7所示。
However, for this example a different access path is selected, which is shown in Figure 7.
因此，其中一条访问路径的中断不会影响从主机发起的存储访问。
So, any interruption to one of the access path does not affect storage access from the host.
请参考本系列之前的文章，了解更多阅读和理解访问路径的文章。
Refer to the previous article of this series for more information about reading and understanding access paths.
这个简单的步骤可能产生新的访问路径，可能显著改进查询性能。
That simple step could lead to a new access path that might dramatically improve query performance.
清单3中的SQL语句创建如图 3所示的访问路径图
The SQL statement in Listing 3 creates the access path graph shown in Figure 3.
您可以从基础访问路径图中的表节点的表描述符处获得该统计信息。
You can obtain the statistics from the table descriptor of the table node in the underlying access path graph.
她温柔地问了问路人甲，之后她身后司机让她进去，于是她改变线路。
"She asks softly of someone off-camera, then changes lanes when the driver behind her lets her in."
她温柔地问了问路人甲，之后她身后司机让她进去，于是她改变线路。
"She asks softly of someone off-camera, then changes lanes when the driver behind her lets her in."
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