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Combine tables

Combine Area and Reader if Area has no reason for existence It can happen that a table has no reason to exist, after denormalisation.

An example: All elements from the table Area have been copied to reader.

Introduction 1. Scope 2. Logical Design
3. Technical Optimisation
Goal Optimisation steps Use ranges Denormalise
Combine tables
Store derived data Add indexes Sort 4. Implementation End
Attention Check if the table is really redundant. Attention: The upper table, 'Area' can have a number of reasons to exist:
  1. an area can exist without readers (a one without manies). For example as input suport, to show a list of all area when adding a new reader.
  2. an area is required for validation or input support, for example a list of valid postcodes.
  3. the table is reuired for other functions.
Next: Store derived data