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 1. Introduction
 2. A Simple Query
 Practice
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 6. Aggregate Fcns.
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 11. Conclusion

More Practice Queries

Write queries to answer the astronomy questions in Practice 3 and 4. Use the Object Browser when you need it.

Practice 3. What are the reddest galaxies in the area of sky near ra = 220?

Write a query to search for galaxies between ra = 219 and ra = 221 brighter than
g = 18.0 for which u - g > 2.2. Retrieve the Object ID, ra, dec, and the five final magnitudes.

Practice 4. What are the highest-redshift quasars in the SDSS database?

Write a query to search for quasars for which we have obtained spectra (search the specObj table) with redshifts greater than 3 and high-confidence measurements. Be sure to retrieve both quasars and the objects classified as high-redshift quasars. Retrieve each quasar's Photo ID, ra, dec, and redshift.

How many results do you get? Do you see any that might be false data?

Answers

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