Write the trigger-function using an untrusted language like PL/TclU, PL/PerlU, or PL/PythonU. (Note the 'U' at the end...) You can call arbitrary commands within an untrusted language. With the regular trusted languages (such plpgsql, PL/Perl or the like) you can't call external programs.
Last edited by loquin; 07-30-09 at 16:18.
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