Normalization process is process to obtain relationship scheme property’s that is nicely becomes higher normal form so that conditions under this fulfilled:
- loop of data which is not necessarily. Redundancy cannot be eliminated at all because good for integrity referential, but redundancy in optimalisation can. For data amounts which are not too much might not too influential in the case of usage hard disk. But imagined if there is thousands, even millions of redundancy, possibly will hardly having an in with space usage.
- Eliminates anomaly. Anomaly basically is un-consistency (inconsistency). Takes example there are commutation of name of from Bank “Maju” becomes Bank “Maju Terus” counted 4 records. If commutation of name of only done at one of record only, hence happened un-consistency that is one relationship bank numbers with 2 name of different bank.
Decomposition tables of can lessen the redundancy and eliminates anomaly.
Scheme through normalization process has advantages as follows:
a. minimization of Storage measure needed to by data storage.
b. minimization of Risk inconsistency data at data base.
c. Minimization possibility that renewal anomaly.
d. Maximizes data structures stability.
Purpose of normalization process is convert relationship to become higher normal form. There is having immeasurable level of normal form, that is :
a. First normal form (1NF)
b. Second normal form (2NF)
c. Third normal form (3NF)
d. Normal Form Boyce-Codd (BCNF)
e. Fourth normal form ( 4NF)
f. Fifth normal form ( 5NF)
First Normal Form
Second Normal Form
Third Normal Form
Normal form third has rule must have is in the form of normal second ( 2NF) and relationship may not load functional dependence among attributes is not main.
Normal Form Boyce-Codd ( BCNF)
Fourth Normal Form
Fifth Normal Form