1.How to debug the procedure ? 
Ans:- You can use DBMS_OUTPUT oracle supplied package or DBMS_DEBUG package.

2.What is difference between stored procedures and application procedures,stored function and application function?
Ans:-
Stored procedures are sub programs stored in the database and can be called & execute multiple times where in an application procedure is the one being used for a particular application same is the way for function

Stored Procedure/Function is a compiled database object, which is used for fast response from Oracle Engine.Difference is Stored Procedure must return multiple value and function must return single value .


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