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copied!<p>YQL requires the xpath expression to evaluate to an itemPath rather than node text. But once you have an itemPath you can project various values from the tree </p> <p>In other words an ItemPath should point to the Node in the resulting HTML rather than text content/attributes. YQL returns all matching nodes and their children when you select * from the data.</p> <p>example </p> <pre><code>select * from html where url="http://stackoverflow.com" and xpath='//div/h3/a' </code></pre> <p>This returns all the a's matching the xpath. Now to project the text content you can project it out using </p> <pre><code>select content from html where url="http://stackoverflow.com" and xpath='//div/h3/a' </code></pre> <p>"content" returns the text content held within the node. </p> <p>For projecting out attributes, you can specify it relative to the xpath expression. In this case, since you need the href which is relative to a.</p> <pre><code>select href from html where url="http://stackoverflow.com" and xpath='//div/h3/a' </code></pre> <p>this returns <code><results> <a href="/questions/663973/putting-a-background-pictures-with-leds"/> <a href="/questions/663013/advantages-and-disadvantages-of-popular-high-level-languages"/> .... </results> </code></p> <p>If you needed both the attribute 'href' and the textContent, then you can execute the following YQL query: </p> <pre><code>select href, content from html where url="http://stackoverflow.com" and xpath='//div/h3/a' </code></pre> <p>returns:</p> <pre><code><results> <a href="/questions/663950/double-pointer-const-issue-issue">double pointer const issue issue</a>... </results> </code></pre> <p>Hope that helps. let me know if you have more questions on YQL.</p>

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