Sloan Digital Sky Survey
SkyServer DR15  
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SQL Tutorial
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 1. Introduction
 2. A Simple Query
 3. Common Searches
 4. More Samples
 5. Multiple Tables
 6. Aggregate Fcns.
 7. Group By
 8. Order By
 10. Functions
 11. Conclusion
SQL Tutorial

NOTE: This is a step-by-step tutorial for those new to SQL. If you already know some SQL and want a more in-depth introduction to how SQL applies to SkyServer, see Using SQL with SkyServer.

Another great way to learn SQL is to modify and submit queries that other people have already written. To jump right in to modifying queries written by scientists, see the Sample SQL Queries.

Searching for Data: A Tutorial

Did you know that you can search through SkyServer's database for only the objects you are interested in? For example, you might want to find all the bright blue galaxies for which we have obtained spectra. Looking through all the hundreds of millions of SDSS objects with the Navigation tool could take years. But using the right search, you could find 10 bright blue galaxies with spectra in seconds!

If you know how to retrieve the right data, you can ask millions of different questions. Searching SkyServer is an incredibly powerful tool for conducting astronomy research; in fact, many professional astronomers search the data in the same way you can.

In this tutorial, you will learn how to search SkyServer to answer many useful astronomical questions. Do the tutorial at your own pace, and use the links to the right to return to points later in the tutorial. As you work, you may also want to look at the Sample Queries, which are examples of real queries that other people have written to search the database.

Click Next to start learning.