PLS_INTEGER is a PL/SQL data type used for storing signed integers. PLS_INTEGER is defined in the STANDARD package as a subtype (or rather a synonym) of BINARY_INTEGER. Variables declared as PLS_INTEGER can be assigned values between -2**31 to 2**31-1 (-2,147,483,648 to 2,147,483,647).
PLS_INTEGER operations use machine arithmetic, so they are generally faster than NUMBER and INTEGER operations.
DECLARE TYPE my_array_t IS TABLE OF VARCHAR2(100) INDEX BY PLS_INTEGER; ...
 Also see
|Glossary of Terms|