Simple Integer

Simple Integer is introduced in Oracle 11g, its not a new data type but it’s a sub type of PLS_INTEGER. It accepts the values in the range of -2,147,483,648 to 2,147,483,647.

•Nulls are not allowed
declare 
   a simple_integer;
begin
   dbms_output.put_line(a);
end;
/
Output:
ORA-06550: line 2, column 6:
PLS-00218: a variable declared NOT NULL must have an initialization assignment


•Allows Overflow.
e.g:
declare 
   a simple_integer:= 2147483647;
begin
   a:=a+2;
   dbms_output.put_line(a);
end;
/
Output:
-2147483647 

There would be performance boost when simple_integer used in real native compilation.