PL SQL Tutorial
In PL/SQL a every for string literal,constant or number,date,time etc., memory will be allocated, Name is assigned to this memory location is called as a Variable. PL-SQL is statically typed programming language. every variables must be declared before its use. Pl/SQL variables are case-insensitive. Every variable must follow following guidlines
BOOLEAN data type represents logical values.values are TRUE,FALSE and NULL.