Advantages of Packages
The benefits of the Packages are as shown below:
The Packages encapsulate logically associated items, types, and subprograms in the named PL/SQL module. Every package is easy to understand, & the interfaces between the packages are clear, simple, and well defined. This aids the application development.
Easier Application Design
When creating an application, all you require initially is the interface information in the package specification. You can code and gather the specification without its body. Then stored the subprograms that reference the package can be compiled as well. You need not define the package bodies completely until you are ready to complete the application.
With the packages, you can state which items, types, and subprograms are public or private. For illustration, if a package has 4subprograms, 3 might be public and one private. The package hide the explanation of the classified subprogram so that only the package is affected if the definition changes. These simplify the maintenance & enhancement. Also, by hiding the implementation details from the users, you secure the integrity of the package.
The Packaged public variables and cursors continue for the duration of the session. Therefore, they can be shared by all the subprograms which execute in the atmosphere. Also, they permit you to maintain the data across transactions without having to store it in the database.
When you call the packaged subprogram for the first time, the entire package is burdened into the memory. And hence, the later calls to correlated subprograms in the package need no disk I/O. Also, the packages stop cascading dependencies and thereby avoid needless recompiling. For illustration, if you change the definition of a packaged function, the Oracle need not recompile the calling subprograms as they do not depend on the package body.