LESSON 5Joining Tables
One of the most powerful features of SQL is its capability to gather and manipulate data from across several tables. Without this feature you would have to store all the data elements necessary for each application in one table. Without common tables, you would need to store the same data in several tables. Imagine having to redesign, rebuild, and repopulate your tables and databases every time your user needed a query with a new piece of information. The JOIN statement of SQL enables you to design smaller, more specific tables that are easier to maintain than larger tables. By the end of the lesson, you will understand and be able to do the following:
• Perform an equi-join.
• Perform a non-equi-join.
• Perform an inner ...
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