Oracle Tips by Burleson

Procedures, Functions and Exception Handling

In Chapters 1 and 2 the PL/SQL code examples have all been using anonymous or un-named blocks. This chapter introduces two of PL/SQL’s named block types, the stored procedure and the function.  A third PL/SQL block type, the trigger, is discussed in Chapter 5, Bulk Operations, Packages and Triggers.  The primary difference between named and unnamed blocks is how the database handles them.  When an unnamed block is sent to the database, it compiles and executes that block.  When a named block is sent to the database, it compiles and stores the block as a database object.  To execute the named block, it must be called.

Procedures  and functions  allow you to modularize and reuse code.  By taking commonly used code and placing it in a separate block, it can be called many times while residing in one location.  This allows the developer to create the code once and provides one location where the code is maintained.  It also allows the programmer to encapsulate the complexity of the application in easy to understand modules.   

The above book excerpt is from:

Easy Oracle PL/SQL Programming

Get Started Fast with Working PL/SQL Code Examples

ISBN 0-9759135-7-3   

John Garmany 

http://www.rampant-books.com/book_2005_1_easy_plsql.htm