Perl for Oracle DBAs

Chapter 8. Embedding Perl into PL/SQL

PL/SQL is Oracle’s own programming language. It©’s a powerful procedural language that is tightly integrated with SQL (“PL/SQL” stands for “Procedure Language extension to Structured Query Language”). It offers a full range of datatypes, conditional and sequential control, looping, exception handling, modular code constructs, user-defined datatypes (such as objects), and a lot more. It’s likely that you have a whole raft of PL/SQL programs that you use daily to perform Oracle database administration.

With all of its advantages, PL/SQL has a few limitations as well. There are things PL/SQL programmers want to do that turn out to be impossible, or at least inefficient, to do with PL/SQL alone. As you might suspect, we think Perl is the ideal supplement to PL/SQL. By calling Perl modules from your PL.SQL programs (more accurately, by embedding Perl within PL/SQL), your PL/SQL programs acquire many additional capabilities:

Mailing and the Internet

It is sometimes difficult to email or connect to the Internet from within PL/SQL, but there are hundreds of helpful connectivity options available through Perl.

Encryption

PL/SQL offers very little built-in security, but Perl provides access to many different types of encrypted security systems. (Later in this chapter we’ll show how we use the MD5 message digest algorithm from within PL/SQL via Digest::MD5.)

Operating system commands

Every now and again — perhaps while running complex backup maneuvers ...