I suggest you, instead of asking someone to give you homework and then you will learn, you start studying from the basics. Like
1. what is Join
2. what are the types of Joins
3. How to use them
4. When to use which join
5. What is the difference between ON clause and Where clause.
6. What is Group by clause, having clause, when to use where and having etc.
This is just a simple list. There is a lot you can do with SQL.
As as starting reference you can refer to :
1.
Best starting tutorial[
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2.
A bit advanced topics[
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3.
A good tutorial on joins[
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4.
One from MSDN[
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If you want to start with examples only then refer :
1.
http://www.itl.nist.gov/div897/ctg/dm/sql_examples.htm[
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