A package in Oracle is a collection of related functions, procedures, and other program objects organized into a single compilation unit. Packages provide modularity, easier application design through privilege management, performance improvements through bulk loading into memory, and the ability for functions and procedures to share variables. A package has two parts - a specification defining the interfaces and a body defining the implementation. Packages are created using the CREATE PACKAGE statement and components are called using the package name and dropped using the DROP PACKAGE statement.

1. PACKAGES

2. Introduction
• A package is a collection of stored functions,
procedures and exceptions.
• A package is compiled and stored in database as
an object.

3. Advantages of Packages
• Modularity -All related functions and procedures can be
grouped together into a single unit called “package”.
• Easier application design – Packages ease the process
of granting privileges. A privilege given on a package
passes on to all the functions and procedures within it.
• Overloading: Packages enable to perform “overloading”
of functions and procedures.
• Improves Performance: Packages improve performance
by loading the multiple objects into memory at once,
therefore calls to related programs do not require physical
I/O.
• Sharing of variables: All the functions and procedures
within a package can share variables among them

4. COMPONENTS OF PACKAGES
• A package comprises 2 parts:
• A specification : It contains the list of various
functions/procedure names which will be a part of the
package.
• A body : This contains the actual PL/SQL code
implementing the logics of functions and procedures
declared in “specification”.

5. Creating a Package-SYNTAX
CREATE [OR REPLACE] PACKAGE package_name {IS|
AS}
Procedure_or_function_specification_1;
Procedure_or_function_specification_2;
End [package_name];
/
CREATE [OR REPLACE] PACKAGE body package_name
{IS|AS}
Procedure_or_function_body_1;
Procedure_or_function_body_2;
End [package_name];
/

6. Calling Package functions and
procedures
• A procedure/function within a package can be called by using
the foll. syntax:
CALL package_name.{procedure_name}
Within a calling program, invoking can be done as follows:
begin
package_name.procedure_name
End;
begin
Variable:=package_name.function_name
End;

7. DROPPING PACKAGE
To drop a package, the foll. syntax is used:
Drop package package_name;
Eg:
Drop package pack1;