Do you use PL/SQL

I will be teaching a PL/SQL class, and I wanted to get some opinions. I read about PL/SQL, but wanted some practical advice from people who have used it.

1. Why use PL/SQL instead of just sending SQL queries from a program written in a procedural language on the client side (Java, Visual Basic, C++, anything.)
2. What are some examples of "real-world" things that you have done with PL/SQL (or have heard some one do with PL/SQL?)

thanks.

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