Simple cross join

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Let's practice what we learned about joins by combining rows from different tables.

Suppose you are a Data Analyst at Lyft, a ride-sharing platform. For a project, you were given three tables:

• trips: trips information
• riders: user data
• cars: autonomous cars

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1. Examine the three tables:

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What’s the primary key of trips?

What’s the primary key of riders?

What’s the primary key of cars?

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3. Try out a simple cross join between riders and cars. Is the result useful?