A Procedure can have a return statement to return the control to the calling block, but, it cannot return any values through the return statement. They cannot be called directly from Select statements but they can be called from another block or through EXEC keyword.
The procedure can be called in the following ways:
a) CALL <procedure name> direc
b) EXCECUTE <procedure name> from calling environment
c) <Procedure name> from other procedures or functions or packages
Functions can be called in the following ways
a) Execute<Function name> from calling environment. Always use a variable to get the return value.
b) As part of an SQL/PL SQL Expression
