Datatypes in Oracle PL/SQL

A scalar data type can have subtypes. A subtype is a data type that is a subset of another data type, which is its base type. A subtype has the same valid operations as its base type. A data type and its subtypes comprise a data type family.

PL/SQL predefines many types and subtypes in the package STANDARD and lets you define your own subtypes.

The PL/SQL scalar data types are:

•          The SQL data types
•          BOOLEAN
•          PLS_INTEGER
•          BINARY_INTEGER
•          REF CURSOR
•          User-defined subtypes

BOOLEAN:
                We cannot pass a Boolean value to DBMS_OUTPUT.PUT or DBMS_OUTPUT.PUT_LINE functions. To print Boolean value, we need to use CASE or IF Statement.

PLS_INTEGER & BINARY_INTEGER:
                PLS_INTEGER requires less storage
                PLS_INTEGER uses hardware arithmetic, so they are faster than NUMBER operations, which uses Library Arithmetic
                SIMPLE _INTEGER is the sub type of PLS_INTEGER . Is it the PLS_INTEGER value with NOT NULL constraint
                BINARY_INTEGER is the subtype of NUMBER, which uses Library Arithmetic
                Predefined PLS_INTEGER Subtypes are

•          NATURAL
•          NATURALN
•          POSITIVE
•          POSITIVEN
•          SIMPLE_INTEGER