namayana

Database plan process (review)
Gather need user/business
Develop e-r model based on need user/business
Conversion e-r model to customer collection (table)
Customer normalization to cause the loss of anomaly
Implementations to database with make table to every customer that normalization

Database normalization
Normalization data base structure formation process so that a large part ambiguity can be caused.
Normalization stage is begun from lightest stage (1nf) up to tightest (5nf)
Usually only come up with level 3nf or BCNF because enough to produce tables have a certain quality good

why done normalization?
Optimalitation table structures
increase speed
cause the loss of data entering same
efficient in storage media use
decrease redundancy
avoid anomaly (insertion anomalies, deletion anomalies, update anomalies).
data integrity that increased
a table is said good (efficient) or normal if fulfill 3 criteria’s as follows:
if there decomposition table, so decomposition must be guaranteed safe (lossless-join decomposition). mean, after table elaborated / decomposition be new tables, new tables can produce table at first with same exactly.
take care functional dependence at the (time) of data change (dependency preservation).
doesn't break boyce-code normal form (BCNF)
if third criteria (BCNF) can not be fulfilled, so at least table doesn't break normal form third stage (3rd normal form / 3nf).