Normalizing Databases
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Design your database with proper normalization of data. Records that have lots of repeating groups of fields are larger than they need to be. Large records can increase the cost of sorting, and also cause records to span more pages than is necessary, resulting in more page fragmentation and needlessly large databases.
Denormalized table design can be more convenient for some types of client applications. You can use InterBase views and stored procedures to in effect store a denormalized query on the server, for convenient access from client applications. Meanwhile, the physical storage of the data is kept in a more efficient, normalized form.
See the Data Definition Guide for details on views and stored procedures.