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Teach Yourself SQL in 21 Days, Second Edition

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Week 2 At A Glance

What's Covered This Week

Week 1 covered the basic SQL query using the SELECT statement. Beginning with the simplest SELECT statement, you learned how to retrieve data from the database. Then you moved on to the SQL functions, which are useful in converting to money or date formats, for example. You quickly learned that you can retrieve data from a database in many ways. Clauses such as WHERE, ORDER BY, and GROUP BY enable you to tailor a query to return a specific set of records. You can use a join to return a set of data from a group of tables. Subqueries are especially useful when you need to execute several queries, each of which depends on data returned from an earlier query.

Week 2 moves on to the more advanced uses of SQL:


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