Just as perhaps we take movie special effects for granted until we see what the state of the art was in previous eras, so we can't fully appreciate the power of relational databases without seeing what preceded them.
Relational databases allow any table to relate to any other table through means of common fields. It is a highly flexible system, and most modern databases are relational.
Featured in this chapter:
The hierarchical database model
The network database model
The relational database model
Learning basic terms
Table keys and foreign keys
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