There is a complete example (with downloadable .NET source code) here:
http://andy.edinborough.org/C-OAuth-Implementation/
This example implements OAuth to let you take advantage of the higher usage limit of 100,000 requests / day and 10,000 requests / hour.
To create an OAuth key, see So, you want to use some Yahoo! APIs.
The code won't work without a minor change: replace the query for pizza with "show tables".
Update:
YQL didn't work with without appending the following string to the query:
&env=http%3A%2F%2Fdatatables.org%2Falltables.env
The full query string is:
http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20%28%22MSFT%22%29&diagnostics=true&env=http%3A%2F%2Fdatatables.org%2Falltables.env
To obtain a full query URL from a YQL query:
- Browse to the Yahoo YQL query console.
- Create a query, e.g.
select * from yahoo.finance.quotes where symbol in ("MSFT")
- On the base of the page, there is a section under "The Rest Query". Copy this. This URL will work in any browser (or any desktop app that uses YQL).
- Modify the C# source to append the string
&env=http%3A%2F%2Fdatatables.org%2Falltables.env
to the url within the two overloaded QueryYahoo
functions.