yql - 在 YQL 中使用 xpath 从网页获取锚文本

Question

SELECT content FROM html WHERE url="http://en.wikipedia.org/wiki/List_of_United_States_National_Parks_by_state" AND xpath="//a/text()"

不起作用，而

SELECT * FROM html WHERE url="http://en.wikipedia.org/wiki/List_of_United_States_National_Parks_by_state" AND xpath="//a/text()"

做。

SELECT content FROM html WHERE url="http://en.wikipedia.org/wiki/List_of_United_States_National_Parks_by_state" AND xpath="//a"

也有效，似乎 YQL 有错误，还是我遗漏了什么？

Answer 1

这是你想要的？

SELECT content FROM html WHERE url="http://en.wikipedia.org/wiki/List_of_United_States_National_Parks_by_state" AND xpath="//a"

Answer 2

SELECT href
FROM html
WHERE url="http://en.wikipedia.org/wiki/List_of_United_States_National_Parks_by_state"
      AND xpath="//a"

在 YQL控制台上试一试。