"SIMPLE_INTEGER" should be used instead of "PLS_INTEGER"

ORACLE 11g introduced the SIMPLE_INTEGER data type, which is a sub-type of PLS_INTEGER, and covers the same range. There are three main differences between the two types:

• SIMPLE_INTEGER is always NOT NULL. So when the value of the declared variable is never going to be null, you can declare it as SIMPLE_INTEGER.
• You will never face a numeric overflow using SIMPLE_INTEGER because this data type wraps around without giving any error.
• The SIMPLE_INTEGER data type gives a major performance boost over PLS_INTEGER when the code is compiled in "NATIVE" mode, because arithmetic operations on SIMPLE_INTEGER type are performed directly at the hardware level.

Noncompliant Code Example

DECLARE
  v1 PLS_INTEGER; -- Noncompliant
  v2 VARCHAR2(10);
BEGIN
  NULL;
END;
/

Compliant Solution

DECLARE
  v1 SIMPLE_INTEGER := 42;
  v2 VARCHAR2(10);
BEGIN
  NULL;
END;
/