What is YQL?

The Yahoo Query Language is an expressive SQL-like language that lets you query, filter, and join data across Web services. With YQL, apps run faster with fewer lines of code and a smaller network footprint.

Yahoo and other websites across the Internet make much of their structured data available to developers, primarily through Web services. To access and query these services, developers traditionally endure the pain of locating the right URLs and documentation to access and query each Web service.

With YQL, developers can access and shape data across the Internet through one simple language, eliminating the need to learn how to call different APIs.

How Do I Get Started?

  1. Check out the YQL Console.
  2. Complete the The Two-Minute Tutorial.
  3. Read how to access YQL from your application.
  4. Get your API Keys to sign your requests if you need them.
  5. Check out the YQL frequently asked questions (FAQ) for answers to common issues.

Using the API or Web Service

  • YQL Overview

    YQL exposes an SQL-like SELECT syntax that is both familiar to developers and expressive enough for getting the right data. Through the SHOW and DESC commands, we enable developers to discover the available data sources and structure without opening another Web browser.

  • YQL Open Data Tables

    Open Data Tables enable developers to add tables for any data on the Web to our stable of API-specific tables. Using Open Data Tables, anyone can make their data YQL-accessible. If you would like to create an Open Data Table, visit the community page at http://datatables.org.

    Examples:


  • YQL Execute

    Building upon Open Data Tables, the Execute element gives developers full control of how the data is fetched into YQL and how it's presented back to the user. With Execute, developers can build tables that manipulate, change, and sign the URLs to access almost any protected content. This lets YQL access and combine data across a variety of different authenticated services such as Netflix or Twitter. Developers can call multiple services and data sources within Execute to join and mash up data however they desire, letting Yahoo do the work rather than their applications. Data can be tweaked and manipulated into an optimal format for applications to consume.

    Execute elements run server-side JavaScript with E4X (native XML) support. This gives developers a fully functional language that Web developers know, and lets them do almost anything they want with the data. We've added a few new global objects to the language to enable developers to: include JavaScript libraries and code from any URL; fetch data from any URL/Web page; run other YQL commands; and perform data filtering and conversion.

    Examples:

    • CSS selectors for HTML - a CSS selector table for getting data from HTML pages

      use 'http://yqlblog.net/samples/data.html.cssselect.xml' as data.html.cssselect;
      select * from data.html.cssselect where url="www.yahoo.com" and css=".accordion-stories a"

      Try CSS selectors.

  • YQL Insert/ Update/ Delete

    You can use YQL to write and modify data on Web services and applications using SQL keywords: INSERT, UPDATE, and DELETE. These verbs let you manipulate data mapped onto an Open Data Table and enables developers to use Open Data Tables to do the following:

    • insert new update to Yahoo Updates, not just list them
    • add new comments to a blog, as well as read them
    • store data in a remote database
    • INSERT INTO Internet

    Open Data Table (ODT) developers can add support for these verbs into their tables by creating new binding types in their ODT definitions. They can then perform the insert/update/delete on the remote web service by creating an execute element that runs their JavaScript to create the right content payload and send it to the remote service. We've extended the capabilities in our server-side JavaScript, so y.rest() can now POST, PUT and DELETE.

    Try creating a new Yahoo update from the YQL console by following this link:
    INSERT INTO social.updates (guid, title, description) VALUES (me, "Using YQL", "Try YQL, it's fun.");

Attribution Guidelines

Thank you for being a part of Yahoo Developer Network community, that helps Yahoo to be part of your users’ daily habits. Please follow our Attribution Guidelines for Yahoo APIs wherever you use YQL.

Using YQL for Commercial and Non-Commercial Applications

Updated 9/10/2013

Our goal is to make it easy for you to use YQL in the widest possible range of applications. Please read the notice and usage limits described below for more information. If you have additional questions, please read the YQL Terms of Service.

Notice

  • The YQL Service can be used for commercial purposes without prior approval from Yahoo
  • Developers using the YQL Service fetching data from a content provider need to conform to the Terms of Service of the content provider.
  • Please note that data available on the Yahoo! network (e.g., Finance, Weather) is not approved for commercial usage via YQL, unless mentioned otherwise in the Terms of Service.

Usage Limits

  • Per application limit (identified by your Access Key): 100,000 calls per day
  • Per IP limits: /v1/public/*: 2,000 calls per hour; /v1/yql/*: 20,000 calls per hour

Additional Notes

  • All rates and terms of service are subject to change
  • You may also be subject to the underlying rate limits of other Yahoo and 3rd party web services
  • YQL relies on the correct operation of the web services and content providers it accesses
  • Open Source content/data tables are not certified by Yahoo

Please use the YQL Forum for additional information or questions.

Information for Content and API providers

Content or API providers can opt out or restrict YQL access to their data by following the instructions in YQL for Content and API Providers.

Note:

Please remember that it is your responsibility to obtain the necessary permissions from the content or API providers to use their content or services, separate from your use of YQL: neither Yahoo nor your use of YQL cover those permissions.

Support and Community

Questions and suggestions on YQL are discussed on the YQL Developer Community forum. If you have questions or need technical support, please use this forum.