Beginning Java Objects: Chapter 3 Objects and Classes
Objects vs. Database Records
As we mentioned in Chapter 2, when people are learning a new
concept, they automatically try to map that concept to a mental model with which they are
already familiar. Folks who are knowledgeable about relational databases (Sybase, Oracle,
SQL Server, Access, DB2, and the like), therefore, have a tendency to relate the concept
of an object to that of a record in a database. (If you are not familiar with relational
databases, please skip this section.)
The object-record analogy holds up to a point:
- Each class of object is analogous to a table in a relational database
- Each record, or row, in the table is analogous to a different object instance
- Each column in a table corresponds to a different attribute of the associated class
This correlation between objects and records has several flaws, however:
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