Counting arguments passed to SQL or PL/SQL?

Have checked all the on-line FAQs but can't find the answer to this.

Have a PL/SQL script that takes optional arguments for switches and such. I know &1, &2, etc., represent these arguments, but is there a variable that represents the number of arguments?

The problem I'm having is that if a variable is not passed in, then SQL asks for it's value if it is encountered in the script. I need some way of knowing if a variable is set.

Thanks.

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Jeff Wilson
jwilson2000_at_home.com
Eugene, Oregon

(541) 684-8590