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.
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.
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.
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.
在执行过程中创建临时的关键访问路径。
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.
哦！不要停下来问路吧，我相信你肯定能找到去那儿的路。
Aww, don't stop for directions, I'm sure you'll be able to figure out how to get there.
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.
想象一下，如果你可以过目不忘，你就可以不必再去问路了。
Imagine if you could look at something once and remember it forever. You would never have to ask for directions again.
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4中的sql语句创建如图4所示的访问路径图。
The SQL statement in Listing 4 creates the access path graph shown in Figure 4.
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.
清单6中的sql语句创建如图6所示的访问路径图。
The SQL statement in Listing 6 creates the access path graph shown in Figure 6.
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.
具体表现就是提前执行一些工作，比如确定数据库访问路径。
It does this by performing some work ahead of time, such as determining the database access path.
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.
直观地说，访问路径是查询执行的程序说明，其包括三个组件。
Intuitively, an access path is a procedural description of query execution that consists of three components.
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.
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.
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.
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