PL/SQL Data Types

 PL/SQL Data Types  

     Data types define the ways to identify the type of data and their associated operations.

     Types of Data Types :-
      There are 4 types of predefined data types explained as below

  1) Scalar Data Types: 

       A scalar data type is an atomic data type that does not have any internal components.
       Example:-
      CHAR      (fixed length character value between 1 and 32,767 characters)
      VARCHAR2  (variable length character value between 1 and 32,767 characters)
      NUMBER    (fixed-decimal, floating-decimal or integer values)
      BOOLEAN   (logical data type for TRUE FALSE or NULL values)
      DATE      (stores date and time information)
      LONG       (character data of variable length)

 2) Composite Data Types : 

       A composite data type is made up of other data types and internal components that can be easily used and manipulated.
       Example:-
      Record, Associate Array, Nested Table and Varray.

 3) Reference Data Types :  

       A reference data types holds values, called pointers that designate to other program items or data items.
       Example:-
      %type, %rowtype.

 4) Large Object Data Types :  

       A Large Object datatype holds values, called locators, that defines the location of large objects( such as video clips, graphic image) stored out of line.
       Example:-
      BFILE    (Binary file)
      BLOB     (Binary large object)
      CLOB     (Character large object)
      NCLOB    (NCHAR type large object)