把该查询提交给SQL编译器之后，语义阶段展开视图定义，并将它合并到初始的查询中，如下所示。

After the query is submitted to the SQL compiler, the semantics phase expands the view definition and merges it into the original query as shown below.

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在此阶段将合并视图定义，以产生一个更复杂的语句，如图8所示。

During this stage the view definitions are merged, resulting in a more complex statement as shown in Figure 8.

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您可以通过忽略某个阶段或合并整个生命周期从而对执行顺序进行修改。

You can change the order of execution by skipping phases or leaving the lifecycle altogether.

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When these two merges are done, we're basically at a stage in that branch where we can now merge those two together, which gives us that, and it goes through the rest of it.

拿到从那边得到的第二个子列表，这是一个基本情况,合并它，当这两个合并完成后，我们基本到了该分支阶段，这里我们可以把两个合并在一起。

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