Normalisation of Database tables and creation of relations.

By bigbaidoo77 ·
I want the process of normalising data and creating relations between tables in access database

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Heres a pretty good explanation

by LocoLobo In reply to Normalisation of Database ...
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Normal Forms

by saiello In reply to Heres a pretty good expla ...

Most small scale databases only require 1st, 2nd and 3rd normal forms to be implemented. These cover common sense requirements when building a database and generally relate to removing redundency in the tables themselves and in the tables that describe relationships to other tables. Work out what 'objects' your database is to hold information about, e.g. Customers, Products, etc, these will directly translate into tables. Next decide what the relationship each of the objects/tables has to eachother, i.e. Customer -> Hires -> Product. Here 'Hires' is the relationship between Customer and Product and will directly translate into a table unto itself. This table will allow the database to keep a record of the '1 to many' relationship between the Customer and how many Products he/she is currently hiring out without repeating Customer or Product information in the database. It will also allow the database to keep a record of the inverse 'many to 1' relationship between Product and Customer, showing how many of this particular product is being hired out by which and how many customers. This is the end result of applying 3rd normal form and will get you, in terms of data storage, a reasonably efficient database. There are 4th, 5th, 6th... normal forms but here were talking the law of diminishing returns and not worth applying for a small database and will just hamper you if you just want to get something up and running..! ;o) The classic book I used at Uni was by C.J.Date "An Introduction To Database Systems", it should still be in print, it's easy to read and gives a good solid ground in normalisation techniques...

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