Datatypes & Normallization

DATA TYPES :

Integer      --  4 bytes

Small int   --  2 bytes

Char(n)      –  N bytes

Varchar(n) –  N+2 bytes

Graph(n)    –  2n bytes

Vargraph(n)–  2N+2 bytes

Date             – 10 bytes

Time            –   8 bytes

Timestamp  –  26 bytes

                       

NORMALIZATION :

Arranging the data in the Database in organized manner.

     1NF:   Avoiding multiple values or set of values in one column.

     2NF:   Avoiding repeated rows by defining primary key.                   

     3NF:   Separating functionally dependent and non-functionally dependent columns