通过定义视图而不是显式的表，可以避免垂直模式的主要缺点，即许多查询要求它与本身进行联结，而这种操作是很昂贵的。

By making a view, rather than an explicit table, we avoid the main disadvantage of a vertical schema, namely that many queries require it to be joined with itself, which can be expensive.

youdao

因为这是一个内联结，所以这个视图不包含出现在wells表中但没有出现在wells _ pts表中的记录(因为这些记录具有空的或无效的坐标)。

Since this is an inner join, this view has no rows for records that appear in Wells but not in wells_pts (because they have null or invalid coordinates).

youdao

另一个问题是横切视图只显示了基于静态联结点shadow的匹配。

Another problem is that the crosscutting views only show matches based on static join point shadows.

youdao