Database Basics

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Onyx uses a relational database model to store data.  This is the industry standard method of storing data and is well documented.  Whilst we couldn’t hope to do the subject justice in just a few short paragraphs, this text may prove useful to anyone who is unfamiliar.  It is also a must if you plan to use the maintenance facilities within Onyx.


Relational database are made up of many tables of information linked to each other to form complex data relationships.  For example, a vehicle record actually draws information from several other tables:




Here you can see that a vehicle record actually has numerous lookups into other tables, hence when we see the final record it has got its colour from the colour table (based upon the matching Colour_ID), the make from the Manufacturers table etc.


This type of model means that the database is not having to store a colour record for every single vehicle (in a table with a thousand green vehicles, this would waste a lot of space), the relational model just stored the word ‘Green’ once and each vehicle record simply has a look up value into the colour table (like an index in a book).


This model allows us great flexibility; imagine a vehicle model is incorrectly spelt (say Tourneo) and nobody notices.  A year later one of your customers happens to comment so you go to rectify the error. If the database was not a relational one, you would have to alter every single Torneo in the vehicle table.  With a relational database, one change to the model table will be reflected system wide.