Summary
This chapter introduces basic relational database concepts. A relational database management system must
Represent all information in the database as tables
Keep the logical representation of data independent from its physical storage characteristics
Use one high-level language for structuring, querying, and changing the information in the database
Support the main relational operations (selection, projection, join) and set operations such as union, intersection, difference, and division
Support views, which allow the user to specify alternative ways of looking at data in tables
Provide a method for differentiating between unknown values (nulls) and zero or blank
Support mechanisms for security and authorization
Protect data integrity through ...
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